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spayn [35]
2 years ago
7

What is the atomic number for an element whose mass number is 78,

Chemistry
2 answers:
Ann [662]2 years ago
5 0

Answer:

protons = atomic numbermass number = protons + neutronsatomic number = mass number - neutrons = 78-38 = 40

Explanation:

murzikaleks [220]2 years ago
4 0

Answer:

48

Explanation:

i took the test lolll

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What is the molarity of a HCl solution that
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Answer:

M = 1.04 M

Explanation:

Given data:

Molarity of solution = ?

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Solution:

Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.

Formula:

Molarity = number of moles of solute / L of solution

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Number of moles = 0.17 mol

Molarity:

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