General Chemistry

Which of the following law states that for elements that can form different compounds, the masses of the second element that can combine with a fixed mass of the first element are in a ratio of small whole number?

• law of multiple proportions

• law of constant composition

• law of conservation of mass

• law of definite proportions

A 10.0 gram of water sample decomposes into 1.11 grams of H2 and 8.89 grams of O2. Which law supports this?

• law of definite proportions

• law of conservation of mass

• law of constant composition

• law of multiple proportions

Tags

NGSS.HS-PS1-7

Who isolated oxygen gas, which he called "dephlogisticated air" by heating mercury oxide (HgO)?

• John Dalton

• Antoine-Laurent Lavoisier

• Joseph Priestly

• Robert Boyle

Who defined "element" as the simplest composition of matter that cannot be broken down further by any chemical means?

• John Dalton

• Joseph Priestly

• Robert Boyle

• Antoine-Laurent Lavoisier

The gases H₂, O₂, and N₂ are considered to be ____.

• atoms

• compound

• mixture

• elements

Tags

NGSS.MS-PS1-1

Which of the following statement does NOT belong to Dalton’s Atomic Theory?

• In chemical reactions, atoms are combined, separated, or rearranged

• Atoms of different elements combine in simple whole-number ratios

• All matter is composed of extremely small particles called atoms

• Atoms can be subdivided, created, or destroyed

Who formulates the law of conservation of mass?

• John Dalton

• Joseph Priestly

• Antoine-Laurent Lavoisier

• Joseph-Louis Proust

Tags

NGSS.HS-PS1-7

If one is to examine samples of carbon dioxide (CO₂) gas from a vehicle in Cavite and carbon dioxide above the pine trees in Baguio, what would be the ratio of each sample?

• A. The ratio of carbon to oxygen in Cavite will be 1:1 while 2:1 in Baguio.

• B. The ratio of carbon to oxygen in Cavite will be 2:1 while 1:1 in Baguio.

• C. Both samples of carbon dioxide will contain the same ratio of carbon to oxygen, which is 1:2.

• D. Both samples of carbon dioxide will contain the same ratio of carbon to oxygen, which is 2:1.

The ratio of the number of hydrogen atoms to the number of oxygen atoms in H2O is _____.

• 1:2

• 2:1

• 1:1:1

• 3:1

Tags

NGSS.MS-PS1-1

13. Analyze these statements. The law of definite proportion suggests that elements combine in specific ratios by mass. It is then apparent that one major difference between atoms of different elements must be their mass.

• Both statements are true.

• Both statements are false.

• The first statement is false and the second statement is true.

• The first statement is true and the second statement is false

Tags

NGSS.HS-PS1-7