Topic 1-3 IB Chemistry SL

Which compound has the empirical formula with the greatest mass?

• C2H6

• C4H10

• C5H10

• C6H6

Under what conditions would one mole of methane gas, CH4, occupy the smallest volume?

• 273 K and 1.01×10⁵ Pa

• 273 K and 2.02×10⁵ Pa

• 546 K and 1.01×10⁵ Pa

• 546 K and 2.02×10⁵ Pa

Which of the following quantities has units?

• Relative atomic mass

• Relative molecular mass

• Molar mass

• Mass number

A reaction occurring in the extraction of lead from its ore can be represented by this unbalanced equation:

__ PbS + __O2 --> __ PbO + __ SO2

When the equation is balanced using the smallest possible whole numbers, what is the coefficient for O2?

• 1

• 2

• 3

• 4

Tags

NGSS.HS-PS1-7

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

• 0.5

• 1

• 2

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

What is the electron arrangement of silicon?

• 2.4

• 2.8

• 2.8.4

• 2.8.8

Tags

NGSS.HS-PS1-1

Which statement is correct for the emission spectrum of the hydrogen atom?

• The lines converge at lower energies.

• The lines are produced when electrons move from lower to higher energy levels.

• The lines in the visible region involve electron transitions into the energy level closest to the nucleus.

• The line corresponding to the greatest emission of energy is in the ultraviolet region.

Tags

NGSS.HS-PS4-3

What is the symbol for a species that contains 15 protons, 16 neutrons and 18 electrons?

• ³¹₁₆S

• ³¹₁₆S^3-

• ³¹₁₅P^-

• ³¹₁₅P^3-

Tags

NGSS.HS-PS1-1

Which statements are correct for the emission spectrum of the hydrogen atom?

I. The lines converge at lower energies.

II. Electron transition to n =1 are responsible for lines in the UV region.

III. Lines are produced when electrons move from higher to lower energy levels.

• I and II only

• I and III only

• II and III only

• I, II and III

Tags

NGSS.HS-PS4-3