All categories

2 years ago

What is the atomic mass of an element if 4.00 grams of it contains 2.98x1022 atoms ?

Chemistry

2 answers:

Klio2033 [76]2 years ago

5 0

Answer:

Atomic mass of the element = 80.80 amu

Explanation:

Given:

Mass of element = 4.00 g

No. of atoms = $2.98\times 10^{22}$

$mol = \frac{No.\ of\ atoms}{Avogadro's\ no.}$

Avogadro's no. = tex]6.02\times 10^{23}[/tex]

$mol = \frac{No.\ of\ atoms}{Avogadro's\ no.}$

= $\frac{2.98\times 10^{22}}{6.02\times 10^{23}} = 0.0495\ mol$

Formula for moles in the terms of mass and atomic mass

$mol = \frac{Mass\ in\ g}{Atomic\ mass} \\Atomic\ mass = \frac{Mass\ in\ g}{mol}$

Atomic mass of the element = $\frac{4.00}{0.0495} = 80.80\ amu$

Atomic mass of the element = 80.80 amu

Sergeu [11.5K]2 years ago

3 0

Hope this helps you.

You might be interested in

Convert 67 inches into a feet

fiasKO [112]

Answer:

Explanation:every feet has 12in so divde, 67/12 so its 5ft 7/12

4 0

2 years ago

How many objects are in a mole of objects?

lakkis [162]

Your Question: {How many objects are in a mole?}

Helpful Knowledge: (We Know the amount in an object: 12g or C^12)

{A number of objects that are in a mole of objects?}

Well for the question it is pretty easy to answer because a number of objects in One mole would equal 6.02 × 10²³

Which 6.02 × 10²³ is an Avogadro's Number.

So it depends on how many objects you have.

So for every object you have, One mole would equal 6.02 × 10²³. Or 62,000,000,000,000,0000,000,000. Big Number am I right. So that's why we just use 6.02 × 10²³.

Anywho, your answer would be 6.02 x 10²³ x n.
N would equal the number of objects you're calculating.

Final Answer: 6.02 x 10²³ x (n) = (Your Answer)

Hope this helps! Have a great day. If you need anything else, feel free to hope right in my inbox. Or comment below. ↓

6 0

2 years ago

A method used by the U.S. Environmental Protection Agency (EPA) for determining the concentration of ozone in air is to pass the

baherus [9]

Answer: 1. $9.08\times 10^{-6}$ moles

2. 90 mg

Explanation:

$O_3(g)+2NaI(aq)+H_2O(l) \rightarrow O_2(g)+I_2(s)+2NaOH(aq)$

According to stoichiometry:

1 mole of ozone is removed by 2 moles of sodium iodide.

Thus $4.54 \times 10^{-6}$ moles of ozone is removed by = $\frac{2}{1}\times 4.54 \times 10^{-6}=9.08\times 10^{-6}$ moles of sodium iodide.

Thus $9.08\times 10^{-6}$ moles of sodium iodide are needed to remove $4.54\times 10^{-6}$ moles of $O_3$

2. $\text{Number of moles of ozone}=\frac{0.01331g}{48g/mol}=0.0003moles$

According to stoichiometry:

1 mole of ozone is removed by 2 moles of sodium iodide.

Thus 0.0003 moles of ozone is removed by = $\frac{2}{1}\times 0.0003=0.0006$ moles of sodium iodide.

Mass of sodium iodide= $moles\times {\text {molar mass}}=0.0006\times 150g/mol=0.09g=90mg$ (1g=1000mg)

Thus 90 mg of sodium iodide are needed to remove 13.31 mg of $O_3$ .

3 0

2 years ago

One tank of gold fish is fed the normal amount of food once a day. A second tank is fed twice a day. A third tank is fed four ti

Arturiano [62]

The question is incomplete, the complete question is;

One tank of goldfish is feed the normal amount which is once a day, a second tank is fed twice a day, and a third tank is fed four times a day during a 6 week study. The fishes' body fat is recorded daily.

Independent Variable-

Dependent Variable-

Constants

Control Group-

Answer:

A) The amount of food the gold fish receives

B) Body fat of the gold fish

C) -Type of fish used in the study (gold fish)

Time period within which the fishes were fed (Six week period)

Shape and size of tank

D) group of gold fish fed the normal amount

Explanation:

The purpose of the study is to determined the impact of amount of feed on the body fat of gold fish. Hence, the amount of feed is the independent variable while the body fat of the feed is the dependent variable.

The control group receives the normal amount of feed (once a day). The fishes are all gold fish, fed within a six week period. All the tanks were of the same shape and size. These are the constants in the study.

4 0

2 years ago

Watered down koolaid is an example of

N76 [4]

The answer is A . Saturated solution

5 0

2 years ago