کیمیا کے بنیادی تصورات

What is the relative atomic mass of oxygen?

• 1 16
• 2 2
• 3 32
• 4 8

How many atoms are present in one molecule of H2SO4?

• 1 3
• 2 9
• 3 5
• 4 7

What is the mass of one mole of water, H2O? (H = 1, O = 16)

• 1 20 g
• 2 18 g
• 3 34 g
• 4 16 g

The number of particles in one mole of any substance is:

• 1 3.01 x 10^23
• 2 1.2 x 10^24
• 3 6.02 x 10^22
• 4 6.02 x 10^23

A substance made of only one kind of atom is called:

• 1 A solution
• 2 A mixture
• 3 An element
• 4 A compound

How many moles are there in 36 g of water? (molar mass 18 g/mol)

• 1 3
• 2 2
• 3 0.5
• 4 1

Which of these is a compound?

• 1 Oxygen
• 2 Iron
• 3 Hydrogen
• 4 Water

The symbol of sodium is:

• 1 S
• 2 Na
• 3 So
• 4 Sd

The formula of carbon dioxide is:

• 1 CO2
• 2 CO
• 3 C2O
• 4 CO3

Which of these is a mixture?

• 1 Water
• 2 Salt
• 3 Air
• 4 Iron

A pure substance made of one kind of atom is a(n):

• 1 Element
• 2 Mixture
• 3 Compound
• 4 Solution

The molar mass of carbon dioxide (C = 12, O = 16) is:

• 1 28 g/mol
• 2 60 g/mol
• 3 44 g/mol
• 4 32 g/mol

How many moles are in 9 g of water? (H = 1, O = 16)

• 1 2 mol
• 2 0.5 mol
• 3 1 mol
• 4 0.9 mol

The number of particles in one mole is:

• 1 6.022 × 10²³
• 2 3.011 × 10²³
• 3 1.66 × 10⁻²⁴
• 4 6.022 × 10²⁰

One mole of any gas at STP occupies:

• 1 11.2 dm³
• 2 22.4 dm³
• 3 44.8 dm³
• 4 1 dm³

The relative atomic mass of an element is measured compared with one twelfth of an atom of:

• 1 Nitrogen-14
• 2 Hydrogen-1
• 3 Oxygen-16
• 4 Carbon-12

An atom that has lost one electron becomes a:

• 1 Anion
• 2 Neutral atom
• 3 Cation
• 4 Molecule

What is the mass of 2 mol of sodium chloride? (Na = 23, Cl = 35.5)

• 1 23 g
• 2 58.5 g
• 3 35.5 g
• 4 117 g

Which of these is a molecule of an element?

• 1 CO₂
• 2 H₂O
• 3 NaCl
• 4 O₂