Chem

Question 1

What is the atomic number of carbon?

Answer 1

6

Question 2

True or False: The pH scale ranges from 0 to 14.

Answer 2

True

Question 3

Fill in the blank: The process of a solid turning directly into a gas is called __________.

Answer 3

sublimation

Question 4

What is the molar mass of water (H2O)?

Answer 4

18.02 g/mol

Question 5

Which type of bond involves the sharing of electron pairs between atoms?

Answer 5

Covalent bond

Question 6

What is the formula for calculating the number of moles from mass?

Answer 6

Moles = mass (g) / molar mass (g/mol)

Question 7

What is the main component of Earth’s atmosphere?

Answer 7

Nitrogen

Question 8

True or False: An exothermic reaction absorbs heat from the surroundings.

Answer 8

False

Question 9

What is the principle of conservation of mass?

Answer 9

Mass is neither created nor destroyed in a chemical reaction.

Question 10

Which gas law states that the volume of a gas is directly proportional to its temperature at constant pressure?

Answer 10

Charles’s Law

Question 11

What is the electron configuration for a sodium atom?

Answer 11

1s² 2s² 2p⁶ 3s¹

Question 12

Fill in the blank: The __________ is the smallest unit of an element that retains the properties of that element.

Answer 12

atom

Question 13

What is the difference between an ionic bond and a covalent bond?

Answer 13

Ionic bonds involve the transfer of electrons, while covalent bonds involve the sharing of electrons.

Question 14

What is the formula for calculating the concentration of a solution?

Answer 14

Concentration = moles of solute / volume of solution (L)

Question 15

True or False: A catalyst increases the activation energy of a reaction.

Answer 15

False

Question 16

What is the primary function of enzymes in biological systems?

Answer 16

To act as catalysts for biochemical reactions.

Question 17

What is the chemical formula for sulfuric acid?

Answer 17

H₂SO₄

Question 18

Which element has the highest electronegativity?

Answer 18

Fluorine

Question 19

What type of reaction is represented by the equation A + B → AB?

Answer 19

Synthesis reaction

Question 20

Fill in the blank: The measure of the randomness or disorder of a system is called __________.

Answer 20

entropy

Question 21

What is Avogadro’s number?

Answer 21

6.022 x 10²³

Question 22

True or False: The boiling point of a substance increases with increasing atmospheric pressure.

Answer 22

True

Question 23

What is the primary type of intermolecular force present in water?

Answer 23

Hydrogen bonding

Question 24

What is the difference between a strong acid and a weak acid?

Answer 24

A strong acid completely dissociates in solution, while a weak acid only partially dissociates.

Question 25

What is the chemical name for NaCl?

Answer 25

Sodium chloride

Question 26

Which law states that the pressure of a gas is inversely proportional to its volume at constant temperature?

Answer 26

Boyle's Law

Question 27

Fill in the blank: The __________ is the energy required to break one mole of bonds in a compound.

Answer 27

bond dissociation energy

Question 28

What is the primary product of the complete combustion of hydrocarbons?

Answer 28

Carbon dioxide and water

Question 29

What type of reaction occurs when an acid reacts with a base?

Answer 29

Neutralization reaction

Question 30

What does the term 'oxidation' refer to in a chemical reaction?

Answer 30

The loss of electrons or an increase in oxidation state.

Question 31

True or False: All metals are good conductors of electricity.

Answer 31

True

Question 32

What is the significance of the octet rule in chemistry?

Answer 32

Atoms tend to gain, lose, or share electrons to achieve a full outer shell of eight electrons.

Question 33

What is the main difference between a saturated and an unsaturated hydrocarbon?

Answer 33

Saturated hydrocarbons contain only single bonds, while unsaturated hydrocarbons contain one or more double or triple bonds.