Q: Which of the following substances will float in water, which has a density of $$1.00\ \text{g/mL}$$? The density of each substance is shown in parentheses.

Olive oil $$(D = 0.92\ \text{g/mL})$$

Q: If the heat of fusion for water is $$80.\ \text{cal/g}$$, how many calories are needed to melt $$30.0\ \text{g} of $$ice at $$0^\circ\text{C}$$?

$$2.4 \times 10^3$\ \text{cal}$$

Question 1

A patient receives a diagnostic test using a radioisotope with a half-life of 6 hours. If the initial dose is 8.0 mg, how much of the radioisotope remains after 24 hours?

Accepted Answer

$$1.0\ 	ext{mg}$$

Question 2

Which of the following best explains why radioisotopes used in medical imaging should have short half-lives?

Accepted Answer

They minimize harmful side effects by decaying quickly.

Question 3

A serving of food contains 30 g carbohydrate (4 kcal/g), 10 g protein (4 kcal/g), and 5 g fat (9 kcal/g). What is the total caloric content?

Accepted Answer

$$215\ 	ext{kcal}$$

Question 4

A metal sample has a mass of 250 g and displaces water from 40.0 mL to 65.0 mL in a graduated cylinder. What is the density of the metal?

Accepted Answer

$$5.0\ 	ext{g/mL}$$

Question 5

Which of the following is a chemical change?

Accepted Answer

Iron rusting

Question 6

A doctor prescribes 0.200 g of a medication. The available suspension contains $$400\ 	ext{mg}/8.0\ 	ext{mL}. $$How many milliliters are needed for the dose?

Accepted Answer

$$4.0\ 	ext{mL}$$

Question 7

Which of the following covalent bonds is the least polar?

Accepted Answer

C-H

Question 8

A sample of ethanol (specific heat $$= 0.59\ 	ext{cal/g}^\circ	ext{C}) $$has a mass of 20 g and is heated from $$15^\circ	ext{C} to$$ $$35^\circ	ext{C}. $$How many calories are absorbed?

Accepted Answer

$$236\ 	ext{cal}$$

Question 9

Which of the following substances will float in water, which has a density of $$1.00\ 	ext{g/mL}$$? The density of each substance is shown in parentheses.

Accepted Answer

Olive oil $$(D = 0.92\ 	ext{g/mL})$$

Question 10

A patient has a temperature of $$39.0^\circ	ext{C}. $$What is this temperature in Fahrenheit?

Accepted Answer

$$102.2^\circ	ext{F}$$

Question 11

Which of the following is a homogeneous mixture?

Accepted Answer

Eye drops

Question 12

Which of the following types of electromagnetic radiation has the highest energy?

Accepted Answer

X-ray

Question 13

The compound FeCl$$_3 is $$named:

Accepted Answer

Iron(III) chloride

Question 14

Which element in Group 4A (14) and Period 3 of the periodic table is used in computer chips?

Accepted Answer

Si

Question 15

What is the correct formula for the oxide ion?

Accepted Answer

$$	ext{O}^{2-}$$

Question 16

Which of the following elements is a noble gas?

Accepted Answer

Argon

Question 17

A nugget of metal with a mass of 386 g is added to 40.0 mL of water, raising the water level to 60.0 mL. What is the density of the metal?

Accepted Answer

$$1.93\ 	ext{g/mL}$$

Question 18

If the heat of fusion for water is $$80.\ 	ext{cal/g}$$, how many calories are needed to melt $$30.0\ 	ext{g} of $$ice at $$0^\circ	ext{C}$$?

Accepted Answer

$$2.4 	imes 10^3$\ 	ext{cal}$$

Question 19

Which one of the following has the highest ionization energy?

Accepted Answer

Cl

Question 20

The temperature of liquid nitrogen is $$-196^\circ	ext{C}. $$What is the corresponding reading on the Kelvin scale?

Accepted Answer

$$77\ 	ext{K}$$

CHEM 114 Exam 1 Study Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard