A 50.0 g sample of a compound contains 1023 molecules Which of the following could be this compound
A 50.0 g sample of a compound contains 2.20 ? 1023 molecules. Which of the following could be this compound?
A) PH3 B) NH3 C) PCl3 D) PCl5 E) NF3
42. A 100.0 g sample of a compound contains 1.37 ? 1024 molecules. Which of the following could be this compound?
A) CO2 B) NH3 C) CH4 D) CCl4 E) CF4
43. If the molar mass of a substance is 34.1 g/mol, what is the mass of 3.01 ? 1024 molecules of the substance?
A) 17.1 g B) 6.82 g C) 8.83 ? 1022 g D) 1.03 ? 1024 g E) 1.70 ? 102 g
44. If the molar mass of a substance is 20.0 g/mol, what is the mass of 3.01 ? 1025 molecules of the substance?
A) 0.400 g B) 10.0 g C) 1.00 ? 103 g D) 6.02 ? 1026 g E) 1.20 ? 1025 g
45. If the molar mass of a substance is 20.0 g/mol, what is the mass of 4.01 ? 1023 molecules of the substance?
A) 30.0 g B) 13.3 g C) 8.02 ? 1024 g D) 1.20 ? 1025 g E) 3.00 g
46. If the molar mass of a substance is 44.01 g/mol, what is the mass of 1.05 ? 1024 molecules of the substance?
A) 76.7 g B) 1.74 g C) 4.62 ? 1025 g D) 4.19 ? 10–23 g E) 25.2 g
47. Calculate the number of moles of NaHCO3 (sodium bicarbonate, or baking soda) in a 5.0 g sample of this substance.
A)0.096 moleD)3.6 ? 1022 moles
B)0.060 moleE)2.8 ? 1023 mole
C)420 moles
48. Calculate the number of moles of NaOH (sodium hydroxide, an ingredient in drain cleaners and oven cleaners) in a 10.0 g sample of this substance.
A)1.51 ? 1023 molesD)4.00 ? 102 moles
B)1.66 ? 1023 moleE)0.250 mole
C)0.208 mole
49. Calculate the number of moles of CaCO3 (calcium carbonate, or limestone) in a 20.0 g sample of this substance.
A)2.00 ? 103 molesD)1.36 ? 103 moles
B)0.200 moleE)1.20 ? 103 moles
C)0.294 mole
50. Calculate the moles of sucrose, C12H22O11, in a 15.0-g sample of this substance.
A)342 molD)4.38 ? 10–2 mol
B)22.8 molE)0.517 mol
C)5.13 ? 103 mol
abhinav behal
15-Feb-2020
