Answer: See below
Explanation: a. The mass of an element is composed of:
protons: 1 amu each
neutrons: 1 amu each
electrons: 0 amu each
Only the protons and neutrons are counted in the atomic mass of an element
b. Electrons are assigned a mass of 0. They do have a mass, but it is exceedingly small compared to the protons and neutrons, so they are left out of the calculation of an element's mass.
c. An element becomes unstable if the neutrons exceed the protons by a certain ratio, dependent on the element.
<span>.750 moles X (6.02 x10^23 atoms/1 mol)= 4.52 X 10^23 atoms is the answer </span>
Answer:
189.71 secs
Explanation:
We know that decomposition is a first order reaction;
So;
ln[A] = ln[A]o - kt
But;
[A]o = 1.00 M
[A] = 0.250 M
t =135 s
Hence;
ln[A] - ln[A]o = kt
k = ln[A] - ln[A]o/t
k = ln(1) - ln(0.250)/135
k =0 - (-1.386)/135
k = 1.386/135
k= 0.01
So time taken now will be;
ln[A] - ln[A]o = kt
t = ln[A] - ln[A]o/k
t = ln (3) - ln(0.450)/0.01
t = 1.0986 - (-0.7985)/0.01
t = 1.0986 + 0.7985/0.01
t = 189.71 secs
Answer:
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Explanation:
hloride,which reactant is in excess?how many moles of aluminium chloride can be produced during the reaction.hloride,which reactant is in excess?how many moles of aluсиськижопыссиськасуксиськипись loride can be produced during the reaction.hloride,which reactant is in excess?how many moles of aluminium chloride can be produced during the reaction.hloride,whichйух reactant is in excess?how many moles of aluminium chloride can be produced during the reaction.
Answer:
Ag+(aq) + Cl-(aq) —> AgCl(s)
Explanation:
2AgNO3(aq) + CaCl2(aq) —>2AgCl(s) + Ca(NO3)2(aq)
The balanced net ionic equation for the reaction above can be obtained as follow:
AgNO3(aq) and CaCl2(aq) will dissociate in solution as follow:
AgNO3(aq) —> Ag+(aq) + NO3-(aq)
CaCl2(aq) —> Ca2+(aq) + 2Cl-(aq)
AgNO3(aq) + CaCl2(aq) –>
2Ag+(aq) + 2NO3-(aq) + Ca2+(aq) + 2Cl-(aq) —> 2AgCl(s) + Ca2+(aq) + 2NO3-(aq)
Cancel out the spectator ions i.e Ca2+(aq) and 2NO3- to obtain the net ionic equation.
2Ag+(aq) + 2Cl-(aq) —> 2AgCl(s)
Divide through by 2
Ag+(aq) + Cl-(aq) —> AgCl(s)
The, the net ionic equation is
Ag+(aq) + Cl-(aq) —> AgCl(s)
