Q: How many significant figures are in the number 0.00700? Write the number in scientific notation.

3 significant figures; $$7.00 \times 10$$^{-3}$$

Q: Round 6585097 to three significant figures. Report the answer in both conventional and scientific notation.

6590000; $$6.59 \times 10$$^{6}$$

Q: How many calories of heat are needed to convert 168 grams of water to steam? (Heat of fusion = 80 cal/g, heat of vaporization = 540 cal/g)

$$168 \times 540 = 90,720$$ cal

Question 1

How many significant figures are in the number 0.00700? Write the number in scientific notation.

Accepted Answer

3 significant figures; $$7.00 	imes 10$$^{-3}$$

Question 2

Round 6585097 to three significant figures. Report the answer in both conventional and scientific notation.

Accepted Answer

6590000; $$6.59 	imes 10$$^{6}$$

Question 3

Convert 4.85 g to kg using dimensional analysis.

Accepted Answer

$$4.85 	imes 10$$^{-3}$$ kg

Question 4

A patient is prescribed 0.250 mg of Synthroid. Each tablet contains 50.0 μg of Synthroid. How many tablets should be given? (1 mg = 1000 μg)

Accepted Answer

5 tablets

Question 5

If the prescribed dose of an antibiotic is 125 mg per kg of body mass, how many grams of antibiotic should be administered to a 175 lb patient? (1 lb = 454 g)

Accepted Answer

$$10.0 g$$

Question 6

Find the volume of 65.0 g of aluminum (density = 2.70 g/cm$$^3).$$

Accepted Answer

$$24.1$$ $$cm^3$

Question 7

Which of the following best describes air?

Accepted Answer

Homogeneous mixture

Question 8

Classify the change: Gunpowder exploding.

Accepted Answer

Chemical change

Question 9

Is snow melting an endothermic or exothermic process?

Accepted Answer

Endothermic

Question 10

What phase change occurs during boiling?

Accepted Answer

Liquid to gas

Question 11

How many calories of heat are needed to convert 168 grams of water to steam? (Heat of fusion = 80 cal/g, heat of vaporization = 540 cal/g)

Accepted Answer

$$168 	imes 540 = 90,720$$ cal

Question 12

What is the molar mass of $$Fe_2$$($$SO_4)_3$?

Accepted Answer

$$399.9 g/$$mol

Question 13

Balance the following reaction: $$C_4H_{10} + O_2$ \rightarrow CO_2$ + H_2O$$

Accepted Answer

$$2C_4H_{10} + 13O_2 \rightarrow 8CO_2 + 10H_2O$$

Question 14

Calculate the mass of 0.600 moles of iron(III) chloride ($$FeCl_3). ($$Molar mass $$FeCl_3 = 162.2$ g/mol)

Accepted Answer

$$97.3 g$$

Question 15

How many moles of $$CO_2$$ are formed from 0.800 moles of $$C_6H_{12}O_6$ in the reaction: C_6H$$_{12}$$O_6 + 6O_2$$ \rightarrow 6CO_2 + 6H_2O$$?

Accepted Answer

$$4.8$$ moles

Question 16

Refer to the energy diagram shown. Where is the energy of activation, and is the reaction exothermic or endothermic?

Accepted Answer

The energy of activation is the peak between reactants and products; the reaction is endothermic.

Question 17

In the cylinder with a piston (see image), what happens to the piston when the temperature is increased from 25°C to 80°C?

Accepted Answer

The piston moves up

Question 18

In the cylinder above, what will happen to the pressure inside the cylinder if the piston is raised without changing temperature or the amount of gas? What gas law applies?

Accepted Answer

Pressure decreases; Boyle's Law ($$P_1V_1 = P_2V_2)$$

Question 19

In the setup with a semipermeable membrane separating 10% KCl (A) and 2% KCl (B), which way will water move?

Accepted Answer

From B to A

CHEM 1123 – Comprehensive Final Study Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard