Material World Revision

Question 1

acid + metal → salt + ____

Answer 1

acid + metal → salt + hydrogen gas

Question 2

acid + base → salt + ____

Answer 2

acid + base → salt + water

Question 3

acid + carbonate → salt + _____ + ________

Answer 3

acid + carbonate → salt + water + carbon dioxide

Question 4

hydrochloric acid → _______ salts

Answer 4

hydrochloric acid → chloride salts

Question 5

nitric acid → _____ salts

Answer 5

nitric acid → nitrate salts

Question 6

sulfuric acid → ______ salts

Answer 6

sulfuric acid → sulfate salts

Question 7

what has a sour taste

Answer 7

acid

Question 8

what’s a substance that has a pH below 7?

Answer 8

acid

Question 9

what turns blue litmus paper red?

Answer 9

acid

Question 10

what’s good for food preservation and why?

Answer 10

acids are good for food preservation because they kill germs.

Question 11

what has a bitter/chalky taste?

Answer 11

base

Question 12

what feels slimy/slippery?

Answer 12

base

Question 13

what’s a substance that has a pH above 7?

Answer 13

base

Question 14

what turns red litmus paper blue?

Answer 14

base

Question 15

what substance is good for cleaning and examples of products?

Answer 15

bases are good for cleaning and are in many soaps and drain cleaners.

Question 16

pH scale 1-6

Answer 16

acidic

Question 17

pH scale 7

Answer 17

neutral

Question 18

pH scale 8-14

Answer 18

basic

Question 19

how can you work out the pH level?

Answer 19

taste it
touch it
use an indicator
add different chemicals
use a pH meter

Question 20

what is a cation?

Answer 20

cation - a positively charged metal ion

Question 21

what is an anion?

Answer 21

anion - a negatively charged non metal ion

Question 22

what observations can we see when a chemical change takes place?

Answer 22

colour change
energy released (gets warmer, gets colder)
a new product is made

Question 23

what is a molecule?

Answer 23

molecule - a substance made up of more than one atom that are held together by attractive forces know as chemical bonds.

Question 24

why/how are ionic bonds formed?

Answer 24

ionic bonds are formed due to an attraction between oppositely charged ions. (positive ion + negative ion)

Question 25

what are ionic bonds formed by?

Answer 25

ionic bonds are formed by a cation and an anion.

Question 26

does a positively charged atom gain or lose electrons when forming an ion?

Answer 26

a positively charged atom loses electrons when forming an ion.

Question 27

does a negatively charged atom gain or lose electrons when forming an ion?

Answer 27

a negatively charged atom gains electrons when forming an ion.

Question 28

why do atoms form ions?

Answer 28

atoms form ions in order to have a full valence shell for it to be stable.

Question 29

what is the charge of a metal (positive) ion?

Answer 29

the charge of a metal (positive) ion is the same as the group number

Question 30

what is the charge of a non-metal (negative) ion?

Answer 30

the charge of a nonmetal (negative) ion is 18 minus the group number

Question 31

what suffix do non metal ions/anions have when formed?

Answer 31

suffix: ide

Question 32

what is a mixture?

Answer 32

a mixture contains more than one substance (element or compound) that are not bonded together e.g sea water.

Question 33

what is an element?

Answer 33

an element is a pure substance that only consists of one type of atom. e.g magnesium.

Question 34

what is a compound?

Answer 34

a compound is a pure substance which is formed when two or more different elements chemically combine, e.g water.

Question 35

what does the atomic number represent?

Answer 35

the atomic number represents the number of protons/electrons in an element.

Question 36

what does the atomic mass represent?

Answer 36

the atomic mass represents the number of (protons OR electrons) + neutrons.

Question 37

how do you find the amount of neutrons?

Answer 37

you find the amount of neutrons by taking away the atomic number from the atomic mass. e.g calcium 40-20=20 neutrons. don't forget to ALWAYS round the atomic mass.

Question 38

what is a nucleus?

Answer 38

the nucleus is the positively charged centre core of an atom, containing protons and neutrons.

Question 39

what is an element?

Answer 39

an element is a substance made up of one type of atom. basically a group of atoms e.g iron, calcium.

Question 40

what is an atom?

Answer 40

basic building blocks of matter, being the smallest unit of an element.

Question 41

what is a period on the periodic table?

Answer 41

periods are the horizontal rows on the periodic table.

Question 42

what is a group on the periodic table?

Answer 42

groups are the vertical columns going from group 1 to 18.

Question 43

what are signs that it is a base in acid reaction equations?

Answer 43

oxide hydroxides

Question 44

what is a physical change?

Answer 44

a physical change is a change where no new substances are made. the change is often reversible

Question 45

what is a chemical change?

Answer 45

a chemical change is a change when a new substance is made. the change is not easily reversible.

Question 46

how/why are some atoms neutrally charged?

Answer 46

atoms can be neutrally charged when the number of protons and electrons are the same, cancelling each other out.

Question 47

carbon dioxide → ______ → _______

Answer 47

carbon dioxide → limewater → milky

Question 48

hydrogen gas → _______ → _______

Answer 48

hydrogen gas → lit splint → pop test

Question 49

oxygen gas → ______ → ______

Answer 49

oxygen gas → glowing splint → will relight

Question 50

what observations can be made from carbon dioxide and limewater?

Answer 50

milky

Question 51

what observations can be made from hydrogen gas and lit splint?

Answer 51

'Pop' test

Question 52

what observations can be made from oxygen gas and glowing splint?

Answer 52

will relight

Question 53

what test makes carbon dioxide milky?

Answer 53

limewater test

Question 54

what test makes hydrogen gas pop?

Answer 54

lit splint

Question 55

what test makes oxygen gas relight?

Answer 55

glowing splint

Question 56

what elements make up NaCI and how many?

Answer 56

1 sodium 1 chloride

Question 57

what is an ion?

Answer 57

an ion is an atom or group of atoms that carries a positive or negative electric charge as a result of have gained or lost one more more electrons.