IB Chemistry Stoichiometry multiple choice Past papers based

What is the total number of ions present in the formula, Al2(SO4)3?

• 2

• 3

• 5

• 6

What is the empirical formula of a compound containing 50% by mass of element X (Ar = 20) and 50% by mass of element Y (Ar = 25)?

• XY

• X3Y2

• X4Y5

• X5Y4

Methane, CH4, burns in Oxygen gas to form Carbon Dioxide and water. How many moles of Carbon Dioxide will be formed from 8.0 g of Methane?

• 0.25

• 0.50

• 1.0

• 2.0

A 4 g sample of Sodium Hydroxide, NaOH, is dissolved in water and made up to 500 cm3 of aqueous solution. What is the concentration of the resulting solution?

• 0.1 mol dm–3

• 0.2 mol dm–3

• 0.5 mol dm–3

• 1.0 mol dm–3

Sodium reacts with Water as shown below.

__ Na + __ H2O --> __ NaOH + __ H2

What is the total of all the coefficients when the equation is balanced using the smallest possible whole numbers?

• 3

• 4

• 6

• 7

Tags

NGSS.HS-PS1-7

Calcium Carbonate decomposes on heating as shown below.

CaCO3 --> CaO + CO2

When 50 g of Calcium Carbonate are decomposed, 7 g of Calcium Oxide are formed. What is the percentage yield of Calcium Oxide ?

• 7%

• 25%

• 50%

• 75%

Tags

NGSS.HS-PS1-7

A cylinder of gas is at a pressure of 40 kPa. The volume and temperature (in K) are both doubled. What is the pressure of the gas after these changes?

• 10 kPa

• 20 kPa

• 40 kPa

• 80 kPa

Which solution contains 0.1 mol of Sodium Hydroxide?

• 1 cm3 of 0.1 mol dm–3 NaOH

• 10 cm3 of 0.1 mol dm–3 NaOH

• 100 cm3 of 1.0 mol dm–3 NaOH

• 1000 cm3 of 1.0 mol dm–3 NaOH

The equation for a reaction occurring in the synthesis of Methanol is

CO2 + 3H2 --> CH3OH + H2O

What is the maximum amount of Methanol that can be formed from 2 mol of Carbon Dioxide and 3 mol of Hydrogen?

• 1 mol

• 2 mol

• 3 mol

• 5 mol

Which contains the same number of ions as the value of Avogadro’s constant?

• 0.5 mol NaCl

• 0.5 mol MgCl2

• 1.0 mol Na2O

• 1.0 mol MgO

Tags

NGSS.HS-PS1-7