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2 years ago

13. Which could be true about an unknown sample with a pH of 7? (2 points)

Chemistry

2 answers:

Rasek [7]2 years ago

7 0

Answer: Option (a) is the correct answer.

Explanation:

Substance which show pH less than 7 are acidic in nature. For example, HCl being a strong acid has pH very less than 7.

Substances which show pH greater than 7 are basic in nature. For example, NaOH being basic in nature has pH greater than 7.

Whereas substances which have pH equal to 7 are neutral in nature, that is, they are neither acidic nor basic.

For example, water is neutral in nature.

Thus, we can conclude that the statement it contains only water is true about an unknown sample with a pH of 7.

laiz [17]2 years ago

5 0

The best and most correct answer among the choices provided by your question is the first choice or letter A.

A ph of 7 contains only water.

I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!

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3 years ago

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2 years ago

A 1.2-L container of liquid nitrogen is kept in a closet measuring 1.0m by 1.3m by 2.0m . Assume that the container is completel

MrRissso [65]

Answer:

26.99 % of air that will be displaced

Explanation:

Step 1: Data given

A 1.2-L container of liquid nitrogen is kept in a closet measuring 1.0m by 1.3m by 2.0m

Temperature = 23.5 °C

Atmospheric pressure = 1.2 atm

Liquid nitrogen has a density of 0.807 g/mL

Molar mass of N2 = 28 g/mol

Step 2: Calculate mass of nitrogen

Mass of nitrogen = density * volume

Mass of nitrogen = 0.807 g/mL * 1200 mL

Mass of nitrogen = 968.4 grams

Step 3: Calculate moles of N2

Moles N2 = mass N2 / molar mass N2

Moles N2 = 968.4 grams /28 g/mol

Moles N2 = 34.586 moles

Step 4: Calculate volume

p*V = n*R*T

⇒ p = the the pressure = 1.2 atm

⇒ V = the volume of N2 = TO BE DETERMINED

⇒ n = the number of moles = 34.586 moles

⇒ R = the gas constant = 0.08206 L*atm/K*mol

⇒ T = the temperature = 23.5 °C = 296.65

V = (n*R*T)/p

V = (34.586 * 0.08206 * 296.65)/1.2

V = 701.61 L

Step 5: Calculate the total volume of the chamber

1.0 m * 1.3 m * 2 m = 2.6 m³ = 2600 L

Step 6: Calculate the percent volume displaced

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