Ark Elvin Academy Year 10 Science Study Pack

Spring assessment 2018

Cumulative content – part 2

Name __________________

Chemistry Periodic table Key knowledge The periodic table – history

Three key Scientists contributed to the periodic table in the 1800s: Dalton, Newland and

Mendeleev

Dalton Newland Mendeleev Ordered elements by relative atomic mass

Ordered elements by relative atomic mass. Newland found that each element was similar to the element eight places further on. For example, starting at Li, Be is the second element, B is the third and Na is the eighth element. There were problems e.g. iron (a metal) was in the same group as sulphur and oxygen

Ordered elements by relative atomic mass. Mendeleev switched the order to fit the preoprties of elements e.g. Te and I. iodine has a smaller relative atomic mass than tellerium but had similar properties to the group after Tellerium. Gaps were left to make sure elements of the same properties were in the same group. Gaps indicated the existence of undiscovered elements and allowed Mendellev to predict what the properties might be.

Scientists did not know about atomic strutcure (protons, neutrons and electrons) and

therefore, were unable to order elements by atomic number

Why were Mendeleev’s ideas accepted?

1. Discovery of isotopes – isotopes of the same element have different atomic masses but the

same chemical properties so occupy the same position on the periodic table

2. Discovery of sub-atomic particles

3. Newly discovered elements fit Mendeleev’s predictions

The periodic table – modern

Intro The periodic table has elements in order of their atomic number and organised according to properties.

The name of the periodic table originates as the elements are said to be arranged ‘periodically’ meaning that there are repeating patterns. We now know that the reason why elements in a group have similar properties is because they have the same number of electrons in the outer shell. Groups are the columns and periods are the rows.

Groups

The group number tells you how many electrons are in the outer shell (number of valence

electrons)

Elements in the same group have similar chemical properties and react in a similar way

Periods The period number tells us how many occupied shells (energy levels) there are; each new

period represents another full shell of electrons.

Metals Approximately 4/5 of the elements in the periodic table are metals

Metals are situated on the left and centre of the periodic table

Metals react to form cations (positively charged ions)

Properties

Strong and malleable

High conductivity (thermal and electrical)

o High melting and boiling points

Non metals Approximately 1/5 of the elements in the periodic table are non-metals

Non-metals are situated on the right of the periodic table

Non-metals react to form anions (negatively charged ions)

Group 7 - Halogens

Physical properties Electronic structure Chemical reactions Trends

Non-metals

Fluorine yellow gas

Chlorine green gas

Bromine red-brown

liquid

Iodine dark grey

solid

7 valence electrons

Gain 1 electron to form -

1 anions to form a full

octet

Exist as diatomic

covalent molecules e.g.

Br2

React with hydrogen to

form covalent

molecules e.g. hydrogen

fluoride

Hydrogen + fluorine

hydrogen fluoride

H2 + F2 2HF

Reaction with metals to

form ionic compounds

e.g. sodium bromide

sodium + bromine

sodium bromide

2Na + Br2 2NaBr

React during

displacement reactions.

As the group descends:

1. The elements

become less

reactive

2. Higher melting

and boiling

points

Why are the group 7

elements less reactive at

the bottom of the

group?

The size of the atom

increases because there

are more electron shells

The outer shell is

further away from the

A displacement reaction

is defined as A more

reactive halogen can

displace a less reactive

halogen from an

aqueous solution of its

salt

e.g. chlorine +

potassium iodide

potassium chloride +

iodine

Cl2 + 2KI 2KCl + I2

positive nucleus due to

increased shielding

(increase no. of shells

between the nucleus

and valence shell), so

when an electron is

transferred to the

halogen the attraction is

weaker than at the top

of the group where the

nuclear attraction is

stronger due to less

shielding

Group 1 – Alkali metals

Physical properties Electronic structure Chemical reactions Trends

Metals

Soft

Low density

1 valence electron

Lose an electron to form

+1 cation to form a full

octet

React with water to

form metal hydroxides:

Group 1 metals react

vigorously n water to

form metal hydroxides

which turn the water

blue when universal

indicator is present as

hydroxides are alkaline.

During this reaction

hydrogen gas. The

presence of hydrogen

can be test form using a

lit splint, a positive test

will form a squeaky pop.

Sodium + water

sodium hydroxide +

hydrogen

2Na + 2H2O 2NaOH

+ H2

As the group descends:

1. The elements

become more

reactive

2. Lower melting

and boiling

points

Why are the group 71

elements more reactive

at the bottom of the

group?

The size of the atom

increases because there

are more electron

shells.

The outer shell is

further away from the

positive nucleus due to

increased shielding

(increase no. of shells

Reaction with chlorine

to form ionic

compounds

e.g. sodium chloride

sodium + chlorine

sodium chloride

2Na + Cl2 2NaCl

Reaction with oxygen to

form ionic compounds

e.g. sodium oxide

sodium + oxygen

sodium oxide

4Na + O2 2Na2O

between the nucleus

and valence shell).

When a group 1 atom

reacts it will form a +1

ion and therefore, needs

to lose an electron. As

the group descends the

nuclear attraction

between the positively

charged nuclear and

valence electron

decreases and can be

lost more readily.

Group 0 – Noble gases

Physical properties Electronic structure Trends

Non-metals

Inert

Colourless gases

Non-flammable

He – 2 electrons in the

outer shell which is a

full first energy level

All other noble gases

have 8 electrons in the

valence shell and

therefore have a full

outer shell.

Outer shell is

energetically stable and

therefore, they are inert

(do not need to

lose/gain electrons)

Monoatomic – travel

around as single atoms.

As the group descends:

1. The boiling point of the noble gases increase

Why are the boiling points of the noble gases higher

at the bottom of the group?

The atomic number of each atom increases as the

group descends, meaning there are a greater

number of electrons in each atom leading to greater

intermolecular forces between atoms which require

a greater amount of energy to overcome.

Key questions The periodic table – history

1. Name three scientists who contributed to the periodic table

2. How were the elements in the periodic table first organised?

3. Which scientist improved the periodic table by leaving gaps for elements he hadn’t thought had been

discovered?

4. Why did people begin to accept this structure of the periodic table?

5. Evaluate whether hydrogen has been put in the correct place on an early version of the periodic table

below. Justify your answer.

The periodic table – modern

1. What fraction of the periodic table is made up of metals

2. Define the term period

3. Define the term group

4. In what order are elements in the periodic table organised? E.g. why does carbon come before nitrogen?

5. What is similar about the electronic structure of the elements of group 1 (Li, Na, K etc.)?

6. Name 2 elements in the periodic table that react in a similar way and explain the reason for this.

7. If an element is in group 1, period 3 what does is tell you about the element’s electronic structure?

8. Do metals form positive or negative ions? Why?

9. Do non-metals form positive or negative ions? Why?

10. Complete the table to show the ion formed from each atom.

Element name

and symbol Group

Number of electrons

in outer shell

Will it lose or gain

electrons? How many?

Charge

on ion

Lithium, Li 1 1 Will lose one Li+

Beryllium, Be Be2+

Oxygen, ____ 6 6 Gain two O2-

_________, N

Boron, B

Fluorine,

_______

P3-

Rb+

11. Use the periodic table to name the elements represented by the electronic structures below

Group 7

1. What is another name for the group 7 elements?

2. How many electrons do group 7 elements have on their outer shell?

3. Write the formula for a molecule of chlorine.

4. Which group 7 element

a) Has the highest melting point?

b) Has the lowest boiling point?

5. Why is fluorine the most reactive halogen?

6. Would a displacement reaction take place if chlorine gas was reacted with potassium bromide? Explain

your answer.

7. Write a word and symbol equation for the reaction between bromine and lithium iodide.

8. In the reaction above, identify the two elements and the two compounds.

9. What kind of substance is potassium fluoride?

10. Explain why potassium fluoride has a higher melting point than fluorine.

11. Explain why iodine is less reactive than bromine.

Group 1

1. State the other name for the group 1 elements.

2. How many electrons do group 1 elements have on their outer shell?

3. Describe and explain the trend in the reactivity of group 1 metals as you descend group 1?

4. Which group 1 element is the least reactive? Why?

5. Complete the table to describe the reactions of the first 3 group 1 elements with oxygen, chlorine and

water.

Group 1

Metal

Reaction with

oxygen

Reaction with

chlorine

Reaction with

water

Lithium

Sodium

Potassiu

m

6. Write a word and symbol equation for the reaction between potassium and:

a. Oxygen

b. Chlorine

c. Water

7. Explain what the different state symbols in your equations stand for

8. A student drops 2g of lithium into 150g of water in a beaker. Explain why the mass of the beaker weighs

less than 152g at the end.

9. This question is about the reaction below:

2Li(s) + Cl2(g) 2LiCl(s)

a. Explain why chlorine is a gas at room temperature

b. Under what conditions will lithium chloride conduct electricity?

c. Why does lithium conduct electricity?

Group 0

1. What is another name for the group 0 elements?

2. How is the electron configuration of group 0 elements similar?

3. How does the electron configuration of group 0 elements affect their reactivity?

4. Does neon or krypton have a higher boiling point? What is the trend as you go down the group?

5. Why are the group 0 elements described as monoatomic?

Biology Respiration Key knowledge The importance of respiration Respiration is an examples of an exothermic reaction. An exothermic reaction is deifned as a reaction that releases eergy; it relseases energy from glucose molecules for use in the body.

Aerobic respiration happens all the time in the cells of animals and plants. Most of the reactions involved

happen inside mitochondria, tiny organelles inside the cytoplasm of the cell. The reactions are controlled by

enzymes. What do organisms need energy from respiration for?

1. Chemical reactions to build larger molecules

2. Movement

3. Maintain body temperature

Aerobic respiration

Aerobic respiration is the form of respiration which uses oxygen. It can be summarised by this equation:

Glucose + oxygen → carbon dioxide + water (+ energy)

Energy is shown in brackets because it is not a substance. Notice that:

Glucose and oxygen are used up

Carbon dioxide and water are produced as waste products

Aerobic respiration happens all the time in the cells of animals and plants. Most of the reactions involved

happen inside mitochondria, tiny organelles inside the cytoplasm of the cell. The reactions are controlled by

enzymes. Anaerobic respiration

Glucose is not completely broken down due to a lack of oxygen

Anaerobic respiration transfers less energy

Anaerobic respiration happens in plants, yeast and animals

Human anaerobic respiration

Glucose lactic acid

Anaerobic respiration in plants and yeast

Glucose ethanol + carbon dioxide

Anaerobic respiration in yeast is called fermentation. Fermentation is

important in the manufacturing of break and alcoholic drinks (beer and

wine) Exercise and respiration

During exercise, the body demands more enegry so the rate of respiration increases. The muscles require

energy for the protein fibres to contract.

The heart rate, breathing rate and breath volume all increase to supply the muscles with more oxygen and

glucose for the increase in aerobic respiration.

The heart rate increases as more blood more more

oxygen and glucose is being transported around the body to

the working muscles and carbon dioxide is being removed

from the working muscle cells.

The breathing rate increases to inhale more oxygen and

to exhale carbon dioxide.

During periods of vigorous activity e.g. 100m sprint, the

muscles might not get enough oxygen, so anaerobic

respiration takes plac in the muscle cells.

Anaerobic respiration and oxygen debt

Muscles become fatigued (tired) during long periods of vigorous activity. This means that they stop

contracting efficiently. One cause of this is the build-up of lactic acid (pH 1) in the muscles from anaerobic

respiration. The lactic acid is removed from the muscles by blood flowing through them.

For the muscles to recover, the oxygen debt (due to a lack of oxygen) must be ‘repaid’.

Oxygen debt is the amount of extra oxygen needed to oxidise (react with the accumulated lactic acid) to

carbon dioxide and water – the muscles begin to respire aerobically again. The existence of an oxygen

debt explains why we continue to breathe deeply and quickly for a while after exercise.

Metabolism What is metabolism? Metabolism is the sum of all of the chemical reactions in a cell or in the body What does metabolism involve? The reactions are controlled by enzymes Require energy; the energy is transferred by respiration to make new molecules. Examples or metabolic reations

1. Conversion of glucose to starch, glycogen and cellulose

2. The formation of lipid molecules from a molecule of gylcerol and three molcules

of fatty acids

3. The use of glucose and nitrate ons to form amino acids which are used to

synthesis proteins

4. The breakdown of excess proteins into urea for excretion

Key questions Respiration: aerobic and anaerobic respiration

1. Which type of respiration requires energy?

2. Why do we need to eat more in cold weather?

3. Write a word and balanced symbol equation for aerobic respiration.

4. Compare the processes of aerobic and anaerobic respiration. Give at least three differences.

5. Outline three uses of the energy released in respiration.

6. Using equations, outline the difference between anaerobic respiration in muscles and in

plants/yeast.

7. State two uses of fermentation.

Anaerobic respiration and oxygen debt 1. Explain why the heart rate must increase during exercise.

2. Explain why the breathing rate must increase during exercise. Suggest what happens to the volume

of breath breathed in.

3. Explain what causes cramp and why.

4. Describe what an oxygen debt is.

5. Describe how lactic acid is converted into glucose.

6. An increased cardiac output will provide more oxygen and more glucose to the working muscles.

Explain how this helps athletes during exercise.

Metabolic reactions 1. Name a metabolic reaction that occurs in all cells.

2. Identify the building blocks (monomers) of the following molecules:

- Carbohydrates:

- Lipids:

- Proteins:

3. Explain why glucose is converted to starch in plants, and glycogen in animals.

4. Describe the structure of a lipid.

5. Explain how excess proteins are excreted.

6. Where is the body is lactic acid broken down after exercise?

Biology Digestion Key knowledge Organisation

Cells are the basic building blocks of all organisms. A tissue is a group of cells with a similar structure and

function. Organs are aggregations of tissues performing specific functions. Organs are organised into

organ systems, which work together to form organisms.

In this module, we will learn about the organs that work together to form the digestive system.

Key vocabulary for the digestive system

Annotate the image below with the parts of the digestive system (shaded)

Absorption Digested food entering the blood stream.

Acid A substance. pH number less than 7.

Alimentary

Canal

A continuous tube from the mouth to the anus, which also includes the

oesophagus, stomach, small and large intestine and rectum. Made from

smooth muscle tissue.

Alkali A substance. pH number of more than 7.

Amylase

An enzyme. Digests starch into sugar. Produced by the salivary glands,

pancreas and duodenum.

Anus The last sphincter of the alimentary canal.

Bile A substance. Emulsifies lipids and neutralises gastric acid.

Digestion Breaking down food from larger, complex to smaller, simpler parts.

Emulsify To make into a smooth mixture.

Enzyme A substance. Digests food into smaller, simpler parts.

Excretion A process. Waste leaving an organism. E.g. faeces.

Faeces Undigested food and fibre.

Gall bladder A gland. Stores bile. Injects bile into duodenum.

Gastric acid A substance. Strong acid produced by the stomach. Destroys bacteria on food.

pH 2.

Glands Organs that give out substances. E.g. gall bladder, liver, pancreas and salivary

gland.

Large intestine

(colon)

An organ. Absorbs water and useful salts back into the blood stream and forms

faeces.

Lipase

An enzyme. Digests lipids into fatty acids and glycerol. Produced by the

pancreas and duodenum.

Lipid

Digests into fatty acids and forms a vital part of cell membranes and is used as

a food reserve.

Liver A gland. Produces bile.

Mucus A substance. Thin, slippery, slightly sticky and wet.

Neutral A substance. pH number of exactly 7.

Oesophagus An organ. This is long (25 cm) tube connects the mouth to the stomach.

Pancreas A gland. Produces amylase, lipase and protease.

Peristalsis A process. When the smooth muscle tissue of the alimentary canal wall

contract and relax in wave-like motions, pushing food along.

Protease An enzyme. Digests protein into amino acids. Produced by the pancreas,

stomach and duodenum.

Protein Digests into amino acids. Gets built up again as proteins for growth and repair.

Rectum An organ. Stores faeces.

Saliva A substance. Mostly water and contains amylase.

Salivary gland A gland. Produces saliva and amylase. pH 7.5.

Small intestine An organ. Split into two halves; the duodenum and the ileum. Narrow and long

to increase the time that food spends there, so more nutrients are absorbed.

Starch Digests into sugar. Sent to mitochondria to respire to produce energy.

Stomach

An organ. Stores food, churns food, breaks down protein and produces gastric

acid to destroy bacteria on food.

Villi

Millions of folds that cover the inside of the small intestine. Villi increase the

surface area of the small intestine. Singular: Villus. Each villus a good blood

supply.

Digestive enzymes What are enzymes? Enzymes are biological catalysts that speed up chemical reactions in living organisms. Enzymes in digestion catalyse the breakdown of large insoluble food molecules into smaller soluble food molecules. This is an example of a catabolic (to break down) reaction. Key features of enzymes

1. Large protein structure

2. Contain an active site

3. Specific

4. Enzymes have optimum activity at different pH and temperatures

What is the lock and key theory?

A model use to explain how enzymes work

The chemical that reacts is called the substrate (e.g.) a

protein molecule and it fits into the enzyme’s (e.g. protease)

active site.

In this situation above, the protein would be the ‘lock’ as

the substrate and the protease would be the ‘key’ as the enzyme.

What effects enzyme action?

High temperature and pH can cause enzymes (the active site)

to change shape; the is called denaturing.

An enzyme becomes denatured when the substrate cannot fit

into the active

sit because the

active site has

changed

shape.

Temperature

and pH change the protein structure within the

enzyme.

Enzymes in the digestive system

Name of enzyme Where is it produced Catabolic reaction Amylase Salivary glands and pancreas Starch sugar Protease Stomach, pancreas and small

intestine Protein amino acids

Lipase Pancreas and small intestine Lipids fatty acids

Bile and Digestion Where?

Bile is a liquid made in the liver and stored in the gall bladder

What?

Alkaline to neutralise hydrochloric acid from the stomach

Emulsifies fats to form smaller droplets, increase the surface area for enzymes to act of and therefore,

increasing the rate of digestion.

Required practical

1. Testing for food groups

2. Investigating the effect of pH on the rate of amylase activity

Key questions Digestive system: organs

1. Put the following in order of size (smallest to largest):

Tissue Organ Cell Organ system

___________ ____________ ______________ __________________

2. Describe the difference between a tissue and an organ.

3. Define the tern digestion

4. Name the three tissues of the stomach. Give the function of each.

5. Give an example of a plant organ and state its function.

6. Complete the table to summarise the role of the organs in the digestive system:

Organ Role Salivary glands

Oesophagus Stomach

Liver Pancreas

Small intestine Large intestine

Digestive system: enzymes and chemicals

1. Define the term enzyme

2. State two factors that affect enzyme action

3. Why are enzymes so important for the body?

4. State the optimum temperature for enzyme action

5. Define the term denatured

6. An enzyme has an optimum temperature of 37°C. Describe and explain the effect of increasing

temperature on the rate of this enzyme-controlled reaction.

7. An enzyme has an optimum pH of 7. Describe and explain the effect of pH on the rate of this

enzyme-controlled reaction.

8. What chemical is in the stomach which creates a low pH?

9. Which pH is the optimum for protease and what does it break down?

10. Which pH is the optimum for amylase and what does it break down?

11. Where are carbohydrates broken down?

12. What product is produced on the breakdown of carbohydrates?

13. Stretch it! How are the products of digestion used in respiration?

Enzyme

Large insoluble molecule

the enzyme breaks down

Small soluble

molecule(s) that are formed

Where the enzyme is produced

Where the

enzyme works

Carbohydrase

Fats (lipids)

Amino acids

The role of bile

1. Where is bile made?

2. Where is bile stored?

3. What are the two functions of bile?

4. Describe the role of bile in emulsification

5. Why is it important for emulsification to occur?

Required practical

1. What reagent is used to test for sugars?

2. What is the positive test for sugars?

3. What apparatus do we need to test for sugars?

4. When iodine turns from brown to blue-black, what is this the positive test for?

5. What reagent is used to test for proteins?

6. What is the positive test for proteins?

7. Why is the pH test carried out at 37 degrees?

8. Explain the use of buffer solutions

9. Describe the independent and dependent variables when testing the effect of pH on amylase action

10. What precautions must be taken when handling iodine?

Physics Energy transfer by heating Key knowledge Energy transfer by conduction

- Metals are the best conductors of energy

- Non-metal materials such as wool and fibreglass are the best insulators

- The higher the thermal conductivity of a material, the higher the rate of energy transfer through it

- The thicker a layer of insulating material, the lower the rate of energy transfer through it.

Specific heat capacity

- The specific heat capacity of a substance is the amount of energy needed to change the temperature

of 1kg of the substance by 1 degree.

- Use the equation E = mc∆θ to calculate the energy needed to change the temperature if mass, m by

∆θ.

- The greater the mass of an object, the more slowly its temperature increases when it is heated.

- To find the specific heat capacity, c of a substance, use a joulemeter and a thermometer to measure

∆E and ∆θ for measured mass, then use c = ∆E/m∆θ.

Heating and insulating buildings

- Electric and/or gas heaters and gas or oil-fired central heating or solid-fuel stoves are used to heat

houses,

- The rate of energy transfer from houses can be reduced by using:

Loft insulation

Cavity wall insulation

Double-glazed windows

Aluminium foil behind radiators

External walls with thicker bricks and lower thermal conductivity

Cavity wall insulation material that is used to fill the cavity between the two brick layers of an

external house wall.

Key questions Energy transfer by conduction

1. Explain why steel pans have handles made of wood or platic?

2. Choose a material you would choose to line winter boots

3. Describe how you could carry out a test on three different lining materials. Assumes you

have a thermometer, a stopwatch, and you can wrap the lining round a container of hot

water.

4. Describe an investigation you would carry out to find out how thickness of an insulating

material affects energy transfer through it

Specific heat capacity 1. Define specific heat capacity.

2. What does it mean if a substance A has a higher specific heat capacity than substance B?

3. What is the difference between heat and temperature?

4. Consider 4kg of copper and 4kg of gold, both at 50ᵒC. Which one contains the most heat

energy?

5. Find the change in thermal energy for 3.4kg of bismuth if its temperature is raised by 14ᵒC.

The specific heat capacity of bismuth is 123J/kgᵒC.

6. A block of silver of mass 12.5kg is heated to raise its temperature by 37ᵒC. Find the thermal

energy required. The specific heat capacity of silver is 233J/kgᵒC.

7. Find the mass of a brass object which gains 387J of energy when its temperature is increased by 1.4ᵒC. The specific heat capacity of brass is 380J/kgᵒC.

8. Find the mass of zinc needed to absorb 2300J of energy if it is heated from 50ᵒC to 61ᵒC. Zinc has a specific heat capacity of 387J/kgᵒC

9. A mass of 3.4kg of water gains 6800J of energy. The specific heat capacity of water is 4186J/kgᵒC. Find the temperature change.

10. Lead has a specific heat capacity of 128 J/kgᵒC. Find the temperature change if a mass of 6.2kg of lead has 4500J of thermal energy added to it.

11. A student set up the apparatus below:

She wanted to calculate the thermal energy change over an hour. She knew the specific heat capacity of water is 4200J/kg°C. What other measurements would she need to take?

12. Why would this calculation not give her an exact value for the thermal energy from the Sun?

How could she improve her experiment?

13. As mass and and specific heat capacity are constants. The results should show that energy

transferred is directly proportional to change in temperature. What does that mean? What is

the symbol used to show to variables are directly proportional?

14. The graph below shows the energy transferred as 2 materials are heated:

Calculate the gradient of the line for water. What is the intercept?

Heating and insulating buildings 1. Explain why cavity wall insulation is better than air in the cavity between the walls of a house

2. Explain why fixing aluminium foil to the wall behind a radiator reduces energy transfer through the

wall.

3. Some double-glazed windows have aplastic frame and a vacuum between the panes:

a. Explain why a plastic frames is better than a metal frame

b. State why a vacuum between the panes is better than air.

4. Explain a method to calculate how much energy is saved overtime on installing new insulation.