# Sample problems biomolecules

1. Question: What is the mass in grams of 1 mole of glucose (C₆H₁₂O₆)? Solution: The molar mass of glucose is 180.16 g/mol. Therefore, the mass of 1 mole of glucose is 180.16 grams.

2. Question: How many moles are there in 90 grams of fructose (C₆H₁₂O₆)? Solution: The molar mass of fructose is 180.16 g/mol. So, 90 grams of fructose is 90 g / 180.16 g/mol = 0.5 moles.
3. Question: What is the mass in grams of 2 moles of urea (CH₄N₂O)? Solution: The molar mass of urea is 60.06 g/mol. Therefore, the mass of 2 moles of urea is 2 x 60.06 g/mol = 120.12 grams.
4. Question: How many moles are there in 58 grams of ethanol (C₂H₅OH)? Solution: The molar mass of ethanol is 46.07 g/mol. So, 58 grams of ethanol is 58 g / 46.07 g/mol = 1.26 moles.
5. Question: What is the mass in grams of 1.5 moles of acetic acid (CH₃COOH)? Solution: The molar mass of acetic acid is 60.05 g/mol. Therefore, the mass of 1.5 moles of acetic acid is 1.5 x 60.05 g/mol = 90.075 grams.
6. Question: How many molecules are in 0.5 moles of glycine (C₂H₅NO₂)? Solution: One mole contains 6.022 x 10²³ entities (Avogadro’s number). Therefore, 0.5 moles of glycine contains 0.5 x 6.022 x 10²³ molecules = 3.011 x 10²³ molecules.
7. Question: Calculate the number of molecules in 0.2 moles of aspartic acid (C₄H₇NO₄)? Solution: There are 0.2 x 6.022 x 10²³ = 1.2044 x 10²³ molecules in 0.2 moles of aspartic acid.
8. Question: What is the molar mass of palmitic acid (C₁₆H₃₂O₂)? Solution: The molar mass of palmitic acid is (16 x C) + (32 x H) + (2 x O) = (16 x 12.01 g/mol) + (32 x 1.01 g/mol) + (2 x 16 g/mol) = 256.42 g/mol.
9. Question: How many grams are in 3 moles of lactose (C₁₂H₂₂O₁₁)? Solution: The molar mass of lactose is 342.3 g/mol. Therefore, 3 moles of lactose weigh 3 x 342.3 g/mol = 1026.9 grams.
10. Question: How many moles are in 150 grams of amino acid glycine (C₂H₅NO₂)? Solution: The molar mass of glycine is 75.07 g/mol. So, 150 grams of glycine equals 150 g / 75.07 g/mol = 1.998 moles.
11. Question: How many moles are there in 98 grams of fatty acid stearic acid (C₁₈H₃₆O₂)? Solution: The molar mass of stearic acid is 284.48 g/mol. So, 98 grams of stearic acid equals 98 g / 284.48 g/mol = 0.344 moles.
12. Question: What is the mass of 0.5 moles of steroid cholesterol (C₂₇H₄₆O)? Solution: The molar mass of cholesterol is 386.65 g/mol. Therefore, the mass of 0.5 moles of cholesterol is 0.5 x 386.65 g/mol = 193.325 grams.
13. Question: How many molecules are in 0.4 moles of nucleotide adenine (C₅H₅N₅)? Solution: One mole contains 6.022 x 10²³ entities. So, 0.4 moles of adenine contain 0.4 x 6.022 x 10²³ molecules = 2.4088 x 10²³ molecules.
14. Question: Calculate the number of moles in 165 grams of nucleotide guanine (C₅H₅N₅O). Solution: The molar mass of guanine is 151.13 g/mol. Therefore, 165 grams of guanine equals 165 g / 151.13 g/mol = 1.091 moles.
15. Question: How many grams are in 1.5 moles of ribose sugar (C₅H₁₀O₅)? Solution: The molar mass of ribose is 150.13 g/mol. Therefore, the mass of 1.5 moles of ribose is 1.5 x 150.13 g/mol = 225.195 grams.
16. Question: What is the mass in grams of 1 mole of nucleotide cytosine (C₄H₅N₃O)? Solution: The molar mass of cytosine is 111.10 g/mol. Therefore, the mass of 1 mole of cytosine is 111.10 grams.
17. Question: How many moles are in 340 grams of sucrose (C₁₂H₂₂O₁₁)? Solution: The molar mass of sucrose is 342.3 g/mol. So, 340 grams of sucrose equals 340 g / 342.3 g/mol = 0.993 moles.
18. Question: Calculate the number of molecules in 0.75 moles of nucleotide thymine (C₅H₆N₂O₂). Solution: One mole contains 6.022 x 10²³ entities. So, 0.75 moles of thymine contain 0.75 x 6.022 x 10²³ molecules = 4.5165 x 10²³ molecules.
19. Question: How many moles are in 132 grams of amino acid valine (C₅H₁₁NO₂)? Solution: The molar mass of valine is 117.15 g/mol. Therefore, 132 grams of valine equals 132 g / 117.15 g/mol = 1.126 moles.