what volume of concentrated hcl should be used to prepare 500 ml of a 00 m hcl solution

HESI A2

HESI A2 Chemistry

1. How much concentrated HCl should be used to prepare 500 mL of a 0.100 M HCl solution?

A. 75 mL
B. 100 mL
C. 125 mL
D. 150 mL

Correct answer: B

Rationale: To prepare a 0.100 M HCl solution with a volume of 500 mL, you can use the formula C1V1 = C2V2, where C1 is the concentration of the concentrated HCl solution, V1 is the volume of concentrated HCl solution used, C2 is the desired concentration (0.100 M), and V2 is the final volume (500 mL). Rearranging the formula to solve for V1, you get V1 = (C2V2) / C1. Plugging in the values (0.100 M)(500 mL) / C1 = 100 mL, which means 100 mL of concentrated HCl should be used to prepare 500 mL of a 0.100 M HCl solution. Therefore, the correct answer is 100 mL. Choice A (75 mL), Choice C (125 mL), and Choice D (150 mL) are incorrect as they do not match the calculated volume needed to prepare the desired concentration of HCl solution.

2. For a compressible fluid subjected to rapid pressure changes, sound wave propagation becomes important. The speed of sound (c) depends on the fluid's:

A. Density (ρ) only
B. Viscosity (μ) only
C. Density (ρ) and Bulk modulus
D. Density (ρ) and Surface tension (γ)

Correct answer: C

Rationale: In a compressible fluid, the speed of sound (c) depends on both the fluid's density (ρ) and Bulk modulus. Density affects the compressibility of the fluid, while Bulk modulus represents the fluid's resistance to compression and plays a crucial role in determining the speed of sound in a compressible medium. Viscosity and surface tension do not directly impact the speed of sound in a compressible fluid subjected to rapid pressure changes. Therefore, the correct answer is C.

3. What word describes a trip to Hawaii that a vacationer FELT was too short?

A. Ponderous
B. Salacious
C. Ephemeral
D. Erudite

Correct answer: C

Rationale: The word 'ephemeral' means lasting for a very short time. In this context, a vacationer feeling that their trip to Hawaii was too short implies that they found it to be brief or fleeting, making 'ephemeral' the most suitable choice among the options provided. Ponderous means slow and clumsy; salacious means obscene or lustful; erudite means showing great knowledge or learning. These words do not convey the idea of brevity or shortness, unlike 'ephemeral,' which perfectly fits the scenario described.

4. A car travels 240 miles in 4 hours. What is its speed in miles per hour?

A. 50 mph
B. 60 mph
C. 55 mph
D. 75 mph

Correct answer: B

Rationale: To calculate speed, divide the distance traveled by the time taken: 240 miles ÷ 4 hours = 60 mph. Therefore, the correct answer is B. Choice A (50 mph) is incorrect as it results from an incorrect calculation. Choice C (55 mph) and D (75 mph) are also incorrect because they are not the correct result of dividing 240 miles by 4 hours.

5. Find the value of x in the ratio and proportion 18:x=10:300.

A. 16
B. 180
C. 30
D. 540

Correct answer: D

Rationale: To find the value of x, cross multiply in the ratio 18:x=10:300. This gives 18 * 300 = 10 * x. Solving for x, x = 540. Therefore, the correct answer is D. Choice A (16), Choice B (180), and Choice C (30) are incorrect because they do not satisfy the proportion equation 18:x=10:300 when cross multiplied.