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Answer:
1. 0.0154mole of PbS
2. Double displacement reaction
Explanation:
First, let write a balanced equation for the reaction. This is illustrated below:
Pb(CH3COO)2 + H2S —> PbS + 2 CH3COOH
Molar Mass of Pb(CH3COO)2 = 207 + 2(12 + 3 + 12 + 16 +16) = 207 + 2(59) = 207 + 118 = 325g
Mass of Pb(CH3COO)2 = 5g
Number of mole = Mass /Molar Mass
Number of mole of Pb(CH3COO)2 = 5/325 = 0.0154mole
From the equation,
1mole of Pb(CH3COO)2 produced 1mole of PbS.
Therefore, 0.0154mole of Pb(CH3COO)2 will also produce 0.0154mole of PbS
2. The name of the reaction is double displacement reaction since the ions in the two reactants interchange to form two different products
Answer:
B: increase.
Explanation:
When we are considering two gases A and B in a container at room temperature .
We have to find the change on rate of reaction when the number of molecules of gases A is doubled
Let [A]=a and [B]=b
A+B product
Rate of reaction
We know that concentration is increases with increase in number of moles
When the number of molecules of gases A is doubled then concentration of gases A increases.
Therefore ,[A]=2a
Rate of reaction
Hence, the rate of reaction is 2 times the initial rate of reaction.Therefore, the rate of reaction will increase when the number of molecules of gases A is doubled.
Answer: B: increase.
False, gravity is a force, matter has mass and volume.
Answer:
N2
Explanation:
We use the ideal gas equation to calculate the number of moles of the diatomic gas. Then from the number of moles we can get
Given:
P = 2atm
1atm = 101,325pa
2atm = 202,650pa
T = 27 degrees Celsius = 27 + 273.15 = 300.15K
V = 2.2L
R = molar gas constant = 8314.46 L.Pa/molK
PV = nRT
Rearranging n = PV/RT
Substituting these values will yield:
n = (202,650 * 2.2)/(8314.46* 300.15)
n = 0.18 moles
To get the molar mass, we simply divide the mass by the number of moles.
5.1/0.18 = 28.5g/mol
This is the closest to the molar mass of diatomic nitrogen N2.
Hence, the gas is nitrogen gas