Q: Which of the following is the correct formula for calculating the average atomic mass of an element with two isotopes?

$$\text{Average mass} = (\text{mass}_1 \times \text{abundance}_1) + (\text{mass}_2 \times \text{abundance}_2)$$

Q: Which of the following is the correct formula for density?

$$\text{Density} = \frac{\text{mass}}{\text{volume}}$$

Question 1

Which of the following is the correct scientific notation for the number 0.00037?

Accepted Answer

$$3.7 	imes 10$$^{-4}$$

Question 2

A sample of water is heated from $$20^\circC to$$ $$100^\circC. If $$the specific heat of water is $$4.18 \ \mathrm{J/g \cdot ^\circ C}$$ and the mass of the sample is $$50 \ \mathrm{g}$$, how much energy is required for this temperature change?

Accepted Answer

$$16,720 \ \mathrm{J}$$

Question 3

Which of the following statements best describes a chemical property?

Accepted Answer

Iron reacts with oxygen to form rust.

Question 4

Which SI unit is used to measure temperature?

Accepted Answer

Kelvin ($$K)$$

Question 5

A student measures the mass of a metal sample as $$12.5 \ \mathrm{g}$$ and its volume as $$2.5 \ \mathrm{cm}^3. $$What is the density of the metal?

Accepted Answer

$$5.0 \ \mathrm{g/cm}^3$$

Question 6

Which of the following is a heterogeneous mixture?

Accepted Answer

Sand and iron filings

Question 7

Which of the following best describes kinetic energy?

Accepted Answer

Energy due to motion

Question 8

Convert $$25^\circC to $$Kelvin.

Accepted Answer

$$298 \ K$$

Question 9

Which of the following is the correct formula for calculating the average atomic mass of an element with two isotopes?

Accepted Answer

$$	ext{Average mass} = (	ext{mass}_1 	imes 	ext{abundance}_1) + (	ext{mass}_2 	imes 	ext{abundance}_2)$$

Question 10

Which of the following elements is an alkali metal?

Accepted Answer

Sodium ($$Na)$$

Question 11

A neutral atom of magnesium ($$Mg) $$has an atomic number of 12 and a mass number of 24. How many neutrons does it have?

Accepted Answer

12

Question 12

Which of the following best describes the process of ion formation?

Accepted Answer

Adding or removing electrons from neutral atoms

Question 13

Which of the following is NOT a derived SI unit?

Accepted Answer

Meter ($$m)$$

Question 14

Which of the following best describes the arrangement of elements in the modern periodic table?

Accepted Answer

By increasing atomic number

Question 15

Which of the following is a physical property?

Accepted Answer

Density

Question 16

If a radioactive isotope has a half-life of 10 years, how much of a 100 g sample will remain after 30 years?

Accepted Answer

12.5 g

Question 17

Which of the following is the correct formula for density?

Accepted Answer

$$	ext{Density} = \frac{	ext{mass}}{	ext{volume}}$$

Question 18

Which of the following types of radiation has the greatest penetrating power?

Accepted Answer

Gamma radiation

Question 19

Which of the following best describes the conservation of energy?

Accepted Answer

Energy cannot be created or destroyed, only converted between forms.

Question 20

A compound has the formula $$H_2O. $$How many atoms are present in one molecule?

Accepted Answer

3

General Biology Study Notes: Measurement, Matter, Energy, and Atomic Structure

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드