Fundamentals of chemistry 1

Question 1

describe the safety symbol for irritant/harmful?

Answer 1

a large x on a yellow triangle

Question 2

what does it mean if you see something with a safety symbol with a skull on it?

Answer 2

toxic

Question 3

what is the relative mass of a neutron

Answer 3

1

Question 4

what is the relative mass of an electron

Answer 4

0

Question 5

what is the electrical charge of an electron ?

Answer 5

-1

Question 6

what is the electrical charge of an neutron?

Answer 6

no charge

Question 7

what is an element?

Answer 7

a substance made up of only on type of atom.

Question 8

what is a compound?

Answer 8

a substance made up of 2 or more elements chemically bonded together

Question 9

what is an atom?

Answer 9

the smallest part of an element that can still be recognized as that element.

Question 10

what is a molecule?

Answer 10

2 or more atoms chemically joined together

Question 11

what is a mixture?

Answer 11

a group 2 or more elements not chemically bonded together.

Question 12

what is the difference between a molecule and a compound?

Answer 12

a compound is 2 or more different types of elements chemically joined together and a molecule is 2 or more atoms chemically joined together

Question 13

where do you find the mass of an atom?

Answer 13

in the nucleus

Question 14

why do atoms have no overall charge?

Answer 14

because there are always the same amount of protons as neutrons, so there cancel each other out

Question 15

where do you find an electron in an atom

Answer 15

in the outer shells

Question 16

what is the formula for water and how many atoms are there in a molecule?

Answer 16

H₂O and 3 atoms are present

Question 17

what is the formula for carbon dioxide

Answer 17

CO₂

Question 18

what is the formula for oxygen?

Answer 18

O₂

Question 19

what equipment is needed to perform the crystilisation of salt water?

Answer 19

bunsen burner, tripod, gauze, evaporating dish and a heat proof mat.

Question 20

which side of a reaction do the reactants go?

Answer 20

on the left

Question 21

how many carbons are there in:
Cu₂(OH)₂(CO₃)₂

Answer 21

2 carbons

Question 22

whats the difference between chemical and physical separation processes

Answer 22

chemical processes are where the chemical structure/formula changes and the physical processes are where the appearance just changes

Question 23

whats the difference between a solute and a solvent?

Answer 23

a solute gets dissolved by the solvent

Question 24

state what the conservation of mass law means?

Answer 24

mass can never be created or destroyed

Question 25

when balancing an equation what do you never change?

Answer 25

the chemical formula

Question 26

what are the state symbols and the names?

Answer 26

S (solid) L (liquid) G(gas) Aq(aquius)

Question 27

why cant simple distillation be used to separate substances with similar boiling points?

Answer 27

as they will both evaporate at the same time and they will not be separated when they condense

Question 28

paper chromatography is used to separate?

Answer 28

mixtures of soluble substances

Question 29

distillation is used to separate?

Answer 29

2 liquids with different boiling points

Question 30

how does paper chromatography work?

Answer 30

it works as the different components travel at different rates. This is because the different substances take different times to disolve in the solvent.The quicker they dissolve, the further they travel up the paper as they have more time.

Question 31

what is Rf value?

Answer 31

The Rf value of a compound is equal to the distance traveled by the compound divided by the distance traveled by the solvent front

Question 32

what is a solution?

Answer 32

a solute dissolved in a solvent

Question 33

what is solubility?

Answer 33

the maximum amount of a substance that will dissolve in a given volume of solvent at a specific temperature

Question 34

___NaCN + ___CuCO₃ --> ___Na₂CO₃ + ___Cu(CN)₂

Answer 34

2 NaCN + 1 CuCO₃ --> 1 Na₂CO₃ + 1 Cu(CN)₂