Caffeine is a bitter stimulant drug and is found in varying quantities in seeds, leaves, and so on. its formula is c8h10n4o2. match the number of moles of each element found in the specified number of moles of caffeine. match the numbers in the left column to the appropriate blanks in the sentences on the right. make certain each sentence is complete before submitting your answer. view available hint(s) 1.6 2.0 4.0 7.0 8.0 10 16 28 1. there are mol of hydrogen in 2.8 mol of caffeine. 2. there are mol of carbon in 2.0 mol of caffeine. 3. there are mol of nitrogen in 0.40 mol of caffeine. 4. there are mol of oxygen in 3.5 mol of caffeine.

1) Answer is: there are 28 moles of hydrogen in 2.8 mol of caffeine.

Caffeine has molecular formula C₈H₁₀N₄O₂.

In one molecule of caffeine there are ten hydrogen atoms:

n(C₈H₁₀N₄O₂) : n(H) = 1 : 10.

n(C₈H₁₀N₄O₂) = 2.8 mol; amount of coffeine molecules.

2.8 mol : n(H) = 1 : 10.

n(H) = 2.8 mol · 10.

n(H) = 28 mol; amount of hydrogen atoms.

2) Answer is: there are 16 moles of carbon in 2.0 mol of caffeine.

In one molecule of caffeine (C₈H₁₀N₄O₂) there are eight carbon atoms:

n(C₈H₁₀N₄O₂) : n(C) = 1 : 8.

n(C₈H₁₀N₄O₂) = 2.0 mol; amount of the coffeine molecules.

2.0 mol : n(C) = 1 : 8.

n(C) = 2.0 mol · 8.

n(C) = 16 mol; amount of the carbon atoms.

3) Answer is: there are 1.6 moles of nitrogen in 0.4 mol of caffeine.

In one molecule of caffeine (C₈H₁₀N₄O₂) there are four nitrogen atoms:

n(C₈H₁₀N₄O₂) : n(N) = 1 : 4.

n(C₈H₁₀N₄O₂) = 0.4 mol; amount of the coffeine molecules.

0.4 mol : n(N) = 1 : 4.

n(N) = 0.4 mol · 4.

n(N) = 1.6 mol; amount of the nitrogen atoms.

4) Answer is: there are 7 moles of oxygen in 3.5 mol of caffeine.

In one molecule of caffeine (C₈H₁₀N₄O₂) there are two oxygen atoms:

n(C₈H₁₀N₄O₂) : n(O) = 1 : 2.

n(C₈H₁₀N₄O₂) = 3.5 mol; amount of the coffeine molecules.

3.5 mol : n(O) = 1 : 2.

n(O) = 3.5 mol · 2.

n(O) = 7 mol; amount of the oxygen atoms.

The amount of hydrogen, carbon, nitrogen, and oxygen in caffeine are 28, 16, 1.6 and 7 moles,

The empirical formula is the smallest comparison of the atoms forming the compound.

Molecular formulas are formulas that show the number of atomic elements that make up a compound.

(empirical formula) n = molecular formula

The principle of determining empirical formulas and molecular formulas

The molecular formula of Caffeine is C₈H₁₀N₄O₂

From this we can see that the mole ratio of each constituent element of caffeine is:

C: H: N: O = 8: 10: 4: 2

Search for moles of forming elements based on the index of elements in the molecule

1. In 2.8 moles of caffeine molecules there is hydrogen = 10 x 2.8 mol = 28 moles

2. In 2.0 moles of caffeine molecules there is carbon = 8 x 2.0 mol = 16 moles

3. In 0.4 moles of caffeine molecules there is nitrogen = 4 x 0.4 mol = 1.6 moles

4. In 3.5 moles of caffeine molecules there is oxygen = 2 x 3.5 mol = 7 moles

the empirical and molecular formulas

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chemical formulas

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The chemical formula for glucose is C6H12O6

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the difference between molecular formula and molecular model

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Keywords: Caffeine molecules, The molecular formula, The empirical formula

it means there are 3 atoms of oxygen