Galena Is the Ore from Which Elemental Lead Is Extracted

question 46

Multiple Choice

Galena is the ore from which elemental lead is extracted. In the first step of the extraction process, galena is heated in air to form lead(II) oxide. 2PbS(s) + 3O₂(g) → 2PbO(s) + 2SO₂(g) ΔH = −827.4 kJ
What mass of galena is converted to lead oxide if 975 kJ of heat are liberated?

• A)203 g
• B)282 g
• C)406 g
• D)478 g
• E)564 g

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Definitions:

Chromosome Theory

The principle that genes are located on chromosomes, which are the basis for heredity and genetic inheritance.

Homologous Chromosomes

Pairs of chromosomes in a diploid organism that are similar in shape, size, and gene content, one inherited from each parent.

Alleles

Alleles are different versions of a gene that determine distinct traits and can be passed from parents to offspring.

Homologous Chromosomes

Homologous chromosomes are pairs of chromosomes in a diploid organism that carry the same genes, one inherited from each parent, but may have different alleles.