Is the normal resting position of an object.

5. At 20°C, the water autoionization constant, Kw, is 6.8 ´ 10–15. What is the H3O+ concentration in neutral water at this tempe

rjkz [21]

Explanation:

Let us assume that the concentration of [ $OH^{-}$ and $H^{+}$ is equal to x. Then expression for $K_{w}$ for the given reaction is as follows.

$K_{w} = [OH^{-}][H^{+}]$

$K_{w} = x^{2}$

$6.8 \times 10^{-15} = x^{2}$

Now, we will take square root on both the sides as follows.

$\sqrt{6.8 \times 10^{-15}} = \sqrt{x^{2}}$

$[H^{+}] = 8.2 \times 10^{-8}$ M

Thus, we can conclude that the $H_{3}O^{+}$ concentration in neutral water at this temperature is $8.2 \times 10^{-8}$ M.

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1. As the temperature of the gas in a balloon decreases, which of the following occurs? The volume of the balloon increases. ***

timama [110]

Answer 1:
Correct Answer: The average kinetic energy of the gas decreases.
Reason:
From the ideal gas equation, we know that PV = nRT
where, P = pressure, V = volume, n = number of moles of gas, R = gas constant and T = temperature.

From above equation, it can be seen that, Temp. as a direct relation with Pressure and Volume. Hence, as temperature of the gas in a balloon decreases, pressure and volume also decreases.

Also, from kinetic theory of gases, we know that, kinetic energy of gas increases with increasing temp. Hence, average kinetic energy of the gas decreases with decreasing temp.

Answer 2:
Correct answer: Out
Reason:
From the ideal gas equation, we know that PV = nRT
where, P = pressure, V = volume, n = number of moles of gas, R = gas constant and T = temperature.

Therefore, when a sealed syringe is heated, it's temp. will increase. This, will result in expansion of gas i.e volume will increase. Hence, syringe plunger move in outwards direction.

Answer 3: Volume = 6046 L
Reason:
From the ideal gas equation, we know that PV = RT
where, P = pressure, V = volume, R = gas constant and T = temperature.
Given: P1 = 99 kPa, V1 = 3000 L, T1 = 312 K, P2 = 45.5 KPa and T2 = 289 K.

Therefore, we have: $\frac{\text{P1 V1}}{\text{P2 V2}} = \frac{\text{R T1}}{\text{R T2}}$
Thus, $\frac{\text{99 3000}}{\text{45.5 V2}} = \frac{\text{R 312}}{\text{R 289}}$

Hence, V2 = 6046 L

Answer 4:
Correct Answer: It increases
Reason:
We know that, pressure of gas, it directly proportional to temp. Hence, when the temp. of as is increases. Total pressure of gas mixture increases. This is because, partial pressure of individual component (in present case oxygen) increases.

Answer 5:
Correct answer: 18.5 kPa
Reason:
We know that, total pressure is the sum of the partial pressures of the gases present in it. Mathematically, it can be expressed as:

Ptot = PO2 + PHe + PCO2

Therefore, partial pressure of oxygen, PO2:

PO2 = Ptot − PHe − PCO2

= 101.4 − 82.5 − 0.4

=18.5 kPa.

Answer 6:

Correct Answer: Argon

Reason:

Inert gases are the best choice for inflating a balloon that must remain inflated for a long period of time. Among given options, both neon and argon are inert gas, But, atomic weight of Ar is 40g/mol, while is more than that of neon (20 g/mol). Hence,. Argon gas is preferred over neon gas.

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Provide the IUPAC names for

ollegr [7]

Answer:

For a: The IUPAC name of the compound is N-ethylethaneamide.

For b: The IUPAC name of the compound is N,N-diethylmethaneamide.

For c: The IUPAC name of the compound is ethyl pentanoate

Explanation:

To name a compound, first look for the longest possible carbon chain.

For a:

Amide group is a type of functional group where an amine group is attached to a carbonyl group. The general formula of amide is $R-CO-NH_2$ , where R is an alkyl or aryl group.

In part (a), the alkyl group has 2 carbon atoms and thus, the prefix used is 'eth-'

Also, an ethyl substituent is directly attached to N-atom. It is an alkane structured hydrocarbon thus, the suffix used will be '-ane'

Hence, the IUPAC name of the compound is N-ethylethaneamide.

For b:

Amide group is a type of functional group where an amine group is attached to a carbonyl group. The general formula of amide is $R-CO-NH_2$ , where R is an alkyl or aryl group.

In part (b), the alkyl group has 1 carbon atoms and thus, the prefix used is 'meth-'

Also, two ethyl substituents are directly attached to N-atom. It is an alkane structured hydrocarbon thus, the suffix used will be '-ane'

Hence, the IUPAC name of the compound is N,N-diethylmethaneamide.

For c:

Esters are a kind of organic molecules having functional groups, $R-COO-R'$ where R and R' are the alkyl or aryl groups. They are formed by the combination of alcohol and carboxylic acid.

These functional group compounds are named in two words which is alkyl alkanoates, where alkyl refers to the alcoholic part and alkanoate refers to the carboxylic acid part of the molecule. The numbering of the parent chain in esters is done from the carboxylic carbon. The alkyl part is not given any numbers.

In part (c), there are 5 carbon atoms present in a straight chain and thus, the prefix used is 'pent-'

Also, an ethyl group forms the alcoholic part.

Hence, the IUPAC name of the compound is ethyl pentanoate

6 0

3 years ago

An infrared light detector would be most beneficial to someone who investigates

Marat540 [252]

Answer:

a

Explanation:

because it works for radiations

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To reduce 16 ounces of a 25% solution of antiseptic to a 10% solution, how much distilled water should a nurse add?

NemiM [27]

Let x = amt of distilled water
:
A simple equation
.25(16) = .10(x+16)
4 = .10x + 1.6

4 - 1.6 = .1x
2.4 = .1x
x = 2.4/0.1
x = 24 oz of distilled water
:
:
Prove this by seeing the amt of antiseptic is the same (only the % changes)
.25(16) = .10(24+16)
4 = .1(40)

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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