Question 1

Which of the following numbers is correctly written in scientific notation?

Accepted Answer

$$1.23 	imes 10^7$

Question 2

Convert $$0.80$$ kilometers to meters. Which of the following is correct?

Accepted Answer

$$8.0 	imes 10^2$ m

Question 3

A block of ice measures $$15 \ \mathrm{cm} 	imes 15 \ \mathrm{cm} 	imes 15 \ \mathrm{cm}. If $$the density of ice is $$0.917 \ \mathrm{g/cm^3$}$$, what is the mass of the block in grams?

Accepted Answer

$$3,090 g$$

Question 4

Which of the following is a chemical change?

Accepted Answer

A match is burned

Question 5

Classify distilled water as an element, compound, or mixture.

Accepted Answer

Compound

Question 6

Which law is illustrated by the statement: 'Heptane is always composed of 84% carbon and 16% hydrogen'?

Accepted Answer

Law of definite proportions

Question 7

When $$18.0$$ grams of water is decomposed by electrolysis, $$16.0 g of $$oxygen and $$2.0 g of $$hydrogen are produced. How much hydrogen should be produced by the electrolysis of $$54 g of $$water?

Accepted Answer

$$6.0 g$$

Question 8

Which scientist is credited with discovering that the mass of an atom is concentrated in the nucleus?

Accepted Answer

Rutherford

Question 9

Which subatomic particle is located outside the nucleus and has a negative charge?

Accepted Answer

Electron

Question 10

How many protons and neutrons are present in the isotope $$^{31}\mathrm{P} ($$Phosphorus-31)?

Accepted Answer

15 protons, 16 neutrons

Question 11

What is the electron configuration of a magnesium atom?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^2$$

Question 12

Which of the following best describes the law of conservation of mass?

Accepted Answer

The total mass of reactants equals the total mass of products in a chemical reaction.

Question 13

Which of the following is a mixture?

Accepted Answer

Milk

Question 14

Which of the following best illustrates the law of multiple proportions?

Accepted Answer

Carbon and oxygen can combine to make either $$\mathrm{CO}_2 or$$ $$\mathrm{CO}.$$

Question 15

Which of the following statements about Group 16 elements (the oxygen group) is correct?

Accepted Answer

They all have six electrons in their outermost shell.

Question 16

A student dissolves sugar in coffee. Which type of change is this, and why?

Accepted Answer

Physical change, because the sugar molecules are dispersed but not chemically altered.

Question 17

Which scientist is credited with determining the mass of the electron?

Accepted Answer

Millikan

Question 18

If $$10 kg is $$equal to $$22.0 lb$$, what is the mass in pounds of a $$5 kg $$object?

Accepted Answer

$$11.0 lb$$

Question 19

Which of the following best describes a proton?

Accepted Answer

Positively charged particle located inside the nucleus

Question 20

Which of the following is true about the electron configuration of Group 16 elements?

Accepted Answer

They all end with $$ns^2$$\ $$np^4 in $$their electron configuration.

Chem 109 Exam 1 Review – Step-by-Step Chemistry Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard