Answer:
195.199grams
Explanation:
Fluorine has a molar mass of 18.99984 while calcium has a molar mass of calcium is 40.08.
1 mole of calcium fluoride has a mass of 40.08+2×18.99984
=78.0797 grams
if one mole has a mass of 78.0797 grams, then 2.5 moles have:
2.5 moles× 78.0797 grams/mole= 195.1992 grams
2.1 x 10²²atoms
Explanation:
Given parameters:
Mass of silver = 3.78g
Unknown:
Number of atoms of silver = ?
Solution:
To solve this problem, we first find the number of moles of the silver from the given mass.
Number of moles = 
Molar mass of Ag = 108g/mole
Number of moles = 
= 0.035mole
Now;
A mole of any substance contains 6.02 x 10²³ atoms
0.035 moles of Ag will contain 0.035 x 6.02 x 10²³ = 2.1 x 10²²atoms
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Number of moles brainly.com/question/13064292
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<h3>
Answer:</h3>
Empirical formula is CrO
<h3>
Explanation:</h3>
<u>We are given;</u>
- Mass of sample of Chromium as 7.337 gram
- Mass of the metal oxide formed as 9.595 g
We are required to determine the empirical formula of the metal oxide.
<h3>Step 1 ; Determine the mass of oxygen used </h3>
Mass of oxygen = Mass of the metal oxide - mass of the metal
= 9.595 g - 7.337 g
= 2.258 g
<h3>Step 2: Determine the moles of chromium and oxygen</h3>
Moles of chromium metal
Molar mass of chromium = 51.996 g/mol
Moles of Chromium = 7.337 g ÷ 51.996 g/mol
= 0.141 moles
Moles of oxygen
Molar mass of oxygen = 16.0 g/mol
Moles of Oxygen = 2.258 g ÷ 16.0 g/mol
= 0.141 moles
<h3>Step 3: Determine the simplest mole number ratio of Chromium to Oxygen</h3>
Mole ratio of Chromium to Oxygen
Cr : O
0.141 mol : 0.141 mol
1 : 1
Empirical formula is the simplest whole number ratio of elements in a compound.
Thus the empirical formula of the metal oxide is CrO
