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3 years ago

An unknown atom has 5

Chemistry

1 answer:

labwork [276]3 years ago

7 0

Answer:

Explanation:

the atomic mass is away protons + neutrons, electrons are neglatable.

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CaF2 + (NH4)2O --> 2 NH4F + CaO How many grams of NH4F can be formed from 34.6 grams of CaF2? (AKS 4f)

bixtya [17]

Answer:

32.83 grams of NH₄F can be formed from 34.6 grams of CaF₂

Explanation:

The balanced reaction is:

CaF₂ + (NH₄)₂O ⇒ 2 NH₄F + CaO

By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), the following quantities participate in the reaction:

CaF₂: 1 mole
(NH₄)₂O: 1 mole
NH₄F: 2 mole
CaO: 1 mole

Being the molar mass of the compounds:

CaF₂: 78 g/mole
(NH₄)₂O: 52 g/mole
NH₄F: 37 g/mole
CaO: 56 g/mole

Then by stoichiometry, the following amounts of mass participate in the reaction:

CaF₂: 1 mole* 78 g/mole= 78 g
(NH₄)₂O: 1 mole* 52 g/mole= 52 g
NH₄F: 2 mole* 37 g/mole= 74 g
CaO: 1 mole* 56 g/mole= 56 g

You can apply the following rule of three: if 78 grams of CaF₂ form 74 grams of NH₄F by stoichiometry, 34.6 grams of CaF₂ will form how much mass of NH₄F?

$mass of NH_{4} F=\frac{34.6 grams of CaF_{2} *74 grams ofNH_{4} F}{78grams of CaF_{2} }$

mass of NH₄F= 32.83 grams

32.83 grams of NH₄F can be formed from 34.6 grams of CaF₂

5 0

3 years ago

A 200-gram sample of a radioactive nuclide is left to decay for 60 hours. At the end of 60 hours, only 25 grams of the sample is

Goryan [66]

Half life is the time taken by a radioactive isotope to decay by half its original mass.
The original mass is 200 g
Time taken is 60 hours
Final mass is 25 g
Therefore;
Final mass = Original mass × (1/2)^n; where n is the number of half lives.
25 = 200 (1/2)^n
1/8 = (1/2)^n
n = 3
Three half lives = 60 hours
1 half lives = 20 hours
Therefore; the half life of the radioactive nucleus is 20 hours

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3 years ago

What is a group of electrons orbiting at roughly the same distance from the nucleus

Alex Ar [27]

A shell of electrons.

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3 years ago

What is the correct answer to the following expression: (72.61 - 68.59) x 18.76? Be sure to express your answer using the correc

ZanzabumX [31]

To answer this expression we should follow the mathematical rule. The mathematical rule that we will follow is called BODMAS short for brackets, powers, divide, multiply, add, subtract. So, we will first solve the one in the brackets which is (72.61 - 68.59) is equal to 4.02 then we will multiply this to 18.76 and the answer is 75.4152.

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3 years ago

How many atoms are in 15.0 moles of C2H6O

Burka [1]

1 mole = 6.22 x 10^23 molecules (Avogadro's number)
15 moles x (6.22 x 10^23) = 9.33 x 10^24 atoms

3 0

3 years ago

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