28)
use:
number of mol = number of atoms / Avogadro’s number
number of mol = 1.81*10^24 / 6.022*10^23 mol
number of mol = 3.01 mol
Answer: 3.01 mol
29)
The given reaction is:
Ca(s) + HCl (g) —> CaCl2 (s) + H2 (g)
Balance Cl:
Ca(s) + 2 HCl (g) —> CaCl2 (s) + H2 (g)
The equation is now balanced
Sum of coefficient = 1 + 2 + 1 + 1 = 5
Answer: B
30)
Molar mass of C9H8O4,
MM = 9*MM(C) + 8*MM(H) + 4*MM(O)
= 9*12.01 + 8*1.008 + 4*16.0
= 180.154 g/mol
mass(C9H8O4)= 0.325 g
use:
number of mol of C9H8O4,
n = mass of C9H8O4/molar mass of C9H8O4
=(0.325 g)/(1.802*10^2 g/mol)
= 1.80*10^-3 mol
Answer: A
Only 1 question at a time please
28) A sample of sulfur contains 1.81 x 1024 atoms of sulfur How many moles of...
30) — 30) A barometer measures A) the difference in pressure between a gas sample and atmospheric pressure. B) the pressure of a gas sample in a container. C) atmospheric pressure. D) the pressure of an ideal gas. E) the difference in pressure between two gas samples. 31) 31) Which one of the following substances, with their structures shown, will NOT display hydrogen bonding? B C.HO D . ethanol E. diethyl ether A. NH, H-N- H HF -E: H H-C-H...
10) How many moles of carbon atoms are there in 0.500 mole of CaH-2 A) 0.500 moles B) 1.00 moles C) 3.00 moles D) 6.02 x 1023 moles E) 4.00 moles 11) How many grams of FerO3 are there in 0.500 mole of FeyOh A) 79.9 g B) 35.9 g C) 63.8 g D) 51.9 g E) 160. g 12) In the kinetic molecular theory of gas behavior, particles of a gas tend to move between them are and collisions...
How many carbon monoxide molecules are there in 2.33 moles of carbon monoxide? 1 O a) 2.02 x 1024 O b) 7.88 x 1023 c) 1.40 x 1024 O d)3.54 x 1024 e) 1.11 x 1022 Which of the following compounds is a covalent compound? 2 Choose all that apply. a) Li2o b) CS2 c) NiCl2 d) NF3 e) Ca3P2 fCsF Which of the following is a property of both solids and gases? 3 a) high degree of compressibility b)...
1. How many atoms are represented by: a. 0.96 moles Ca b. 0.39 moles Ga c. 0.94 moles Ag d. 0.39 moles Mg 2. How may molecules are represented by a. 0.39 moles CH3COOH b. 0.71 moles N2 C. 0.72 moles C&H 206 d. 0.57 moles 02 3. How may grams are represented by: a. 6.11 moles C6H1206 b. 1.89 moles 02 c. 6,61 moles NaHCO3 d. 1.14 moles Na 4. How may moles are represented by: a. 26.32 grams...
5) How many moles of hydrogen gas are needed to react with oxygen to form one mole of 5) water? 2H2(8) + O268) - 2H20(1) A) 4 mol B) 1 mol C) 2 mol D) 0.5 mol E) 6 mol 6) Incomplete combustion occurs when there is insufficient oxygen to react with a compound. The suffocating gas carbon monoxide is a product of incomplete combustion. How many moles of oxygen gas are required for the complete combustion of 11.0 moles...
How many moles of gas are in a gas sample occupying 0.73799999999999999 L at 135 mm Hg and 30° C? A 0.0052700000000000004 mol B 40.5 mol C 190 mol D 0.00043300000000000001 mol E 4.0099999999999998 mol
19. One nanogram does not seem like a very large number. How many magnesium atoms are there in 1.00 ng of magnesium? A) 4.11 x 10 atoms B) 2.48 x 10" atoms C) 6.83 x 10 atoms D) 6.02 x 10" atoms E) 1.46 x 104 atoms 20. How many moles of O atoms are in 25.7 g of CaSO.? A) 0.189 mol B) 0.755 mol C) 4.00 mol D) 1.14 x 10^mol E) 4.55 x 10" mol 21. Balance...
can you please explain the answers 19. One nanogram does not seem like a very large number. How many magnesium atoms are there in 1.00 ng of magnesium? A) 4.11 x 10- atoms B) 2.48 x 10" atoms C) 6.83 x 10" atoms D) 6.02 x 10 atoms E) 1.46 x 10" atoms 20. How many moles of O atoms are in 25.7 g of CaSO.? A) 0.189 mol B) 0.755 mol C) 4.00 mol D) 1.14 x 10” mol...
2. Menerva has 1 mol of AICI. How many moles of ions are there in 1 mol of AICI:? a. I mol i mo 10 lat b. 2 mol miza c. 3 mol d. 4 mol e, 6 mol Answer: 3. Jessica has 64.0 g of sulfur dioxide (SO2). How many oxygen atoms are there in 64.0 g of SO2? a. 64 atoms b. 128 atoms c. 6.022 x 10” atoms d. 1.806 x 10 4 atoms c. 1.204 x...
Please Answer All (Showing work won't be necessary, just the final answer) 10. How many moles of lithium ions are in 353.7 ml of 0.8926 M lithium phosphate? A) 0.2265 mol B) 0.3157 mol C) 0.4050 mol D) 0.4942 mol E) 0.6794 mol F) 0.9471 mol G) 1.215 mol H) 1.483 mol I) none of these 11. What is the name of the acid HBrO4? A) hydrobromic acid B) bromic acid C) bromous acid D) perbromic acid E) hypobromous acid...