Science study flashcards ( term 1 practise )

Question 1

What is the first step in the scientific method?

Answer 1

Make an observation that leads to a question.

Question 2

What must a good investigative question include?

Answer 2

The independent and dependent variables.

Question 3

What is a hypothesis?

Answer 3

A possible answer to the investigative question that includes the variables.

Question 4

What is a control in an experiment?

Answer 4

A factor that does not change or affect results.

Question 5

What are the types of variables in an experiment?

Answer 5

Independent (controlled), Dependent (measured), Controlled (kept constant).

Question 6

What kind of graph is used when both variables change continuously?

Answer 6

Line graph.

Question 7

What does the first column in a data table usually represent?

Answer 7

The independent variable.

Question 8

What is the SI unit for temperature?

Answer 8

Degrees Celsius (°C) or Kelvin (K).

Question 8

Convert 100 cm to meters.

Answer 8

1 meter.

Question 9

Convert 500 000 mg to kg.

Answer 9

0.5 kg.

Question 10

What does the prefix “kilo-“ mean?

Answer 10

1000 times the unit.

Question 11

What comes after the title sheet in a project?

Answer 11

Table of Contents.

Question 12

What section compares your findings to your hypothesis?

Answer 12

Findings, Conclusions and Generalisations.

Question 13

What is an element?

Answer 13

A pure substance that cannot be broken down by chemical methods.

Question 14

What are the vertical columns in the Periodic Table called?

Answer 14

Groups.

Question 15

Name 3 semi-metals.

Answer 15

Boron (B), Silicon (Si), Arsenic (As).

Question 16

What are alkali metals?

Answer 16

Group 1 elements excluding hydrogen.

Question 17

What are transition metals?

Answer 17

Metals between Groups 2 and 13.

Question 18

What are the 3 subatomic particles?

Answer 18

Protons (+), Neutrons (0), Electrons (-).

Question 19

Where are protons and neutrons found?

Answer 19

In the nucleus.

Question 20

How do you calculate the number of neutrons?

Answer 20

N = Mass number (A) - Atomic number (Z)

Question 21

What is a diatomic molecule?

Answer 21

Two identical atoms bonded (e.g., O₂, H₂).

Question 22

What does H₂O stand for?

Answer 22

Water: 2 hydrogen atoms, 1 oxygen atom.

Question 23

What kind of bonding forms molecules?

Answer 23

Chemical (usually covalent) bonds.

Question 24

Name the suffix for oxygen in compounds.

Answer 24

-oxide (e.g., CO₂ = carbon dioxide).

Question 25

What is the charge of an anion?

Answer 25

Negative (gained electrons).

Question 25

What is an ion?

Answer 25

An atom that gained or lost electrons.

Question 26

What is the charge of a cation?

Answer 26

Positive (lost electrons).

Question 27

What do balanced chemical equations show?

Answer 27

The correct ratio of reactants and products.

Question 28

What does the arrow (→) in a chemical equation mean?

Answer 28

"Yields" or "forms".

Question 29

What does (aq) mean in chemical equations?

Answer 29

Aqueous (dissolved in water).

Question 30

What does 2H₂O mean?

Answer 30

Two molecules of water.

Question 31

What is the dependent variable in the table showing the mass of aluminum cubes?

Answer 31

Mass — it depends on the volume of the cubes.

Question 32

What unit is used to measure the melting point of frozen milk?

Answer 32

Degrees Celsius (°C).

Question 33

Which metal can be molten with a flame of 500 °C?

Answer 33

Tin (melting point = 232 °C).

Question 34

Name the subatomic particles in the nucleus of an atom.

Answer 34

Protons and neutrons.

Question 35

What is the molecular formula of water?

Answer 35

H₂O

Question 36

What is the difference between an element and a compound?

Answer 36

An element cannot be chemically broken down; a compound is made of two or more elements chemically combined.

Question 37

Write down the formula of a compound that consists of sodium, carbon, and oxygen in a 2:1:3 ratio.

Answer 37

Na₂CO₃

Question 38

What is the formula for sulphuric acid?

Answer 38

H₂SO₄

Question 39

How many atoms are there in 3(NH₄)₂CO₃?

Answer 39

N = 6 H = 24 C = 3 O = 9N = 6 H = 24 C = 3 O = 9

Question 40

Which of the following are molecules: Br₂, Ar, SO₃, K, H₂O, Li⁺, HCl, NaCl?

Answer 40

Molecules: Br₂, SO₃, H₂O, HCl

Question 41

Balance this equation: Fe + H₂SO₄ → Fe₂(SO₄)₃ + H₂

Answer 41

2Fe + 3H₂SO₄ → Fe₂(SO₄)₃ + 3H₂

Question 42

Balance: Na + O₂ → Na₂O

Answer 42

4Na + O₂ → 2Na₂O

Question 43

Balance: N₂ + H₂ → NH₃

Answer 43

N₂ + 3H₂ → 2NH₃

Question 44

Balance: Al + O₂ → Al₂O₃

Answer 44

4Al + 3O₂ → 2Al₂O₃

Question 45

Balance: KBr + Cl₂ → KCl + Br₂

Answer 45

2KBr + Cl₂ → 2KCl + Br₂

Question 46

Balance: H₂ + Fe₂O₃ → Fe + H₂O

Answer 46

3H₂ + Fe₂O₃ → 2Fe + 3H₂O

Question 47

Balance: Mg + HCl → MgCl₂ + H₂

Answer 47

Mg + 2HCl → MgCl₂ + H₂

Question 48

Balance: BaCl₂ + Na₂SO₄ → BaSO₄ + NaCl

Answer 48

BaCl₂ + Na₂SO₄ → BaSO₄ + 2NaCl

Question 49

Magnesium + oxygen → magnesium oxide

Answer 49

2Mg + O₂ → 2MgO

Question 50

Iron + oxygen → magnetic iron oxide (Fe₃O₄)

Answer 50

3Fe + 2O₂ → Fe₃O₄

Question 51

Mercury oxide → mercury + oxygen

Answer 51

2HgO → 2Hg + O₂

Question 52

Zinc + hydrochloric acid → zinc chloride + hydrogen

Answer 52

Zn + 2HCl → ZnCl₂ + H₂

Question 53

Sulphuric acid + sodium hydroxide → sodium sulphate + water

Answer 53

H₂SO₄ + 2NaOH → Na₂SO₄ + 2H₂O

Question 54

Lead (II) oxide + carbon → lead + carbon dioxide

Answer 54

2PbO + C → 2Pb + CO₂

Question 55

Copper carbonate + sulphuric acid → copper sulphate + water + carbon dioxide

Answer 55

CuCO₃ + H₂SO₄ → CuSO₄ + H₂O + CO₂