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3 years ago

The heat of vaporization of water is 40.66 kj/mol. how much heat is absorbed when 2.46 g of water boils at atmospheric pressure?

2 answers:

8 0

Change mass to moles. There are 18 grams in one mole of water.

2.45g / 18g = .14 moles of water

The heat absorbed is 40.66 kJ for each mol so

40.66 x .14 = 5.5 kJ

klasskru [66]3 years ago

6 0

<u>Answer:</u> The amount of heat absorbed by water is 5570.42 J

<u>Explanation:</u>

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass of water = 2.46 g

Molar mass of water = 18 g/mol

Putting values in above equation, we get:

$\text{Moles of water}=\frac{2.46g}{18g/mol}=0.137mol$

To calculate the heat absorbed by water, we use the equation:

$\Delta H_{vaporization}=\frac{q}{n}$

where,

$q$ = amount of heat absorbed = ? J

n = number of moles of water = 0.137 moles

$\Delta H_{vaporization}$ = heat of vaporization of water = 40.66 kJ/mol = 40660 J/mol (Conversion factor: 1 kJ = 1000 J)

Putting values in above equation, we get:

$40660J/mol=\frac{q}{0.137mol}\\\\q=(40660J/mol\times 0.137mol)=5570.42J$

Hence, the amount of heat absorbed by water is 5570.42 J

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2 years ago

How many moles are in 3.4 x 10-7 grams of Silicon dioxide, SiO2?

Varvara68 [4.7K]

Answer:

Number of moles = 0.057 × 10⁻⁷ mol

Explanation:

Given data:

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2 years ago

The time necessary for the decay of one- half sample of a radioactive substance is a _____. mass defect daughter half life nucli

Mazyrski [523]

Answer: half life

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$t=\frac{2.303}{k}\hspace{1mm}log\frac{x}{a}$

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k= disintegration constant

x= amount of substance left after time t

a= initial amount of substance

when one half of the sample is decayed, one half of the sample remains and t can be represented as $t_{1/2}$

at $t= t_{1/2}$ , $x=\frac{a}{2}$

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3 years ago

Read 2 more answers

The regular sequence of growth and division that cells undergo is called the?

KIM [24]

Answer:

Cell cycle.

Explanation:

A cell can be defined as the fundamental or basic functional, structural and smallest unit of life for all living organisms. Some living organisms are unicellular while others are multicellular in nature.

A unicellular organism refers to a living organism that possess a single-cell while a multicellular organism has many (multiple) cells.

Generally, cells have the ability to independently replicate themselves. These cells can be compared to the kind of structures found in a business or factory, where you have different workers performing different functions.

In a cell, the "workers" that perform various functions or tasks for the survival of the living organism are referred to as organelles and they include nucleus, cytoplasm, cell membrane, golgi apparatus, mitochondria, lysosomes, ribosomes, chromosomes, endoplasmic reticulum, vesicles, etc.

The regular sequence of growth and division that cells undergo is called the cell cycle. This cycle makes it possible for the cells found in living organisms to divide and produce new cells.

Basically, there are four (4) phases of the cell cycle and these are;

I. Prophase.

II. Metaphase.

III. Anaphase.

IV. Telophase.

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2 years ago

A possible mechanism for the gas phase reaction of NO and H2 is as follows: Step 1 2NO N2O2 Step 2 N2O2 + H2 N2O + H2O Step 3 N2

mel-nik [20]

Answer: Option (d) is the correct answer.

Explanation:

Steps involved for the given reaction will be as follows.

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Rate expression for step 1 is as follows.

Rate = k $[NO]^{2}$

Step 2: $N_{2}O_{2} + H_{2} \rightarrow N_{2}O + H_{2}O$

This step 2 is a slow step. Hence, it is a rate determining step.

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Here, $N_{2}O_{2}$ is intermediate in nature.

All the steps are bimolecular and it is a second order reaction. Also, there is no catalyst present in this reaction.

Thus, we can conclude that the statement step 1 is the rate determining step, concerning this mechanism is not directly supported by the information provided.

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