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Phoenix [80]
2 years ago
11

21. an atom has 216 protons, how many electrons does it have?

Chemistry
1 answer:
yanalaym [24]2 years ago
4 0

Answer:

21: 47 22: 14

Explanation:

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Balance the equation AlCl3 + H2SO4 yields Al2(SO4)3 +HCl
Natalija [7]

Answer:

2AlCl3 + 3H2SO4 → Al2(SO4)3 + 6HCl

Explanation:

3 0
2 years ago
Zachary adds 9.7 g to 1.114 g.<br> How many significant figures should his answer have?
makvit [3.9K]
Always use least amount of sig figs possible. So this 9.7 would be (answer): 2 sig figs
5 0
2 years ago
A 3.82 g piece of limestone contains 2.62 g of CaCO3
Kobotan [32]

Considering the definition of percentage by mass, the mass percentage of CaCO₃ is 68.59%.

<h3>What is mass percentage</h3>

The percentage by mass expresses the concentration and indicates the amount of mass of solute present in 100 grams of solution.

In other words, the percentage by mass of a component of the solution is defined as the ratio of the mass of the solute to the mass of the solution, expressed as a percentage.

The percentage by mass is calculated as the mass of the solute divided by the mass of the solution, the result of which is multiplied by 100 to give a percentage. This is:

mass percentage=\frac{mass of solute}{mass of solution}x100

<h3>Mass percentage of CaCO₃</h3>

In this case, you know:

  • mass of CaCO₃: 2.62 grams
  • mass of limestone: 3.82 grams

Replacing in the definition of mass percentage:

mass percentage=\frac{2.62 grams}{3.82 grams}x100

<u><em>mass percentage= 68.59 %</em></u>

Finally, the mass percentage of CaCO₃ is 68.59%.

Learn more about percentage by mass:

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#SPJ1

7 0
1 year ago
Radon-222 is a radioactive gas with a half-life of 3.82 days. How long would it take for 15/16 of the sample of radon-222 to dec
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Post an image to give solver a visual idea
5 0
3 years ago
Indicate the number of unpaired electrons for following:
Viktor [21]
Ignoring the n's, there would only be one unpaired electron. 
6 0
3 years ago
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