Round 6: Which sample has the largest mass?
A) 5.00 mol of C
B) 1.50 mol of Cl2
C) 0.50 mol of C6H12O6
B) Cl2 has 106 g
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thief
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25
gift
Win 20 points!
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rocket
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lifesaver
Give 15 points!
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thief
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fairy
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shark
Other team loses 20 points!
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lifesaver
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5
Round 3: A small pin contains 0.0178 mol of iron (Fe). How many atoms of iron are in the pin?
1.07 x 10^22 atoms
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baam
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gift
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fairy
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banana
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20
The following reaction proceeds with an 89% yield.
C2H5OBr + NaOH --> C2H4O + NaBr + H2O
What mass of C2H4O can be obtained when 3.61 x 10^23 molecules of C2H5OBr react with excess sodium hydroxide?
23.5 g
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10
Round 2: Rubidium ignites spontaneously when exposed to oxygen to form Rb2O. Rubidium exists as two isotopes: Rb-85 (84.91u) and Rb-87 (86.91u). If the average atomic mass of Rubidium is 85.47u, determine the percentage abundance of Rb-85.
72%
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20
Round 4: A sample of pure acetic acid CH3COOH contains 1.40 x 10^23 carbon atoms. How many moles of acetic acid are in the sample?
0.116 mol
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5
Round 7: Sodium chloride (NaCl) can be used to melt snow. How many moles of sodium chloride are in a 10kg bag?
171.1 mol
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15
Round 16: A hydrate of zinc nitrate has the formula Zn(NO3)2*xH2O. If the mass of 1 mol of anhydrous zinc nitrate is 63.37% of the mass of 1 mol of hydrate, what is the value of x?
Zn(NO3)2*6H2O
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10
Round 14: Olive oil is used widely in cooking. Oleic acid, a component of olive oil, contains 76.54% carbon, 12.13% hydrogen and 11.33% oxygen by mass. What is the empirical formula of oleic acid?
C9H17O1
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10
Round 12: A compound consists of 17.6% hydrogen and 82.4% nitrogen. Determine the empirical formula of the compound.
NH3
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10
Round 9: Find the percentage composition of a pure substance that contains 7.22g nickel, 2.53g phosphorus and 5.25g oxygen.
Ni = 48.1%
O = 35.0%
P = 16.9%
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20
4C3H6(g) + 6NO(g) --> 4C3H3N(g) + 6H2O(g) + N2(g)
What is the limiting reagent when 126 g of C3H6 reacts with 175g of NO?
C3H6
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20
Round 15: Tartaric acid, also known as Cream of Tartar, is used in baking. Its empirical formula is C2H3O3. If 1.00mol of tartaric acid contains 3.61x1024 oxygen atoms, what is the molecular formula of tartaric acid?