Answer : The number of molecules present in nitrogen gas are,
Explanation :
First we have to calculate the moles of nitrogen gas by using ideal gas equation.
where,
P = Pressure of
gas =
(1 atm = 760 mmHg)
V = Volume of
gas = 985 mL = 0.982 L (1 L = 1000 mL)
n = number of moles
= ?
R = Gas constant =
T = Temperature of
gas =
Now put all the given values in above equation, we get:

Now we have to calculate the number of molecules present in nitrogen gas.
As we know that 1 mole of substance contains
number of molecules.
As, 1 mole of
gas contains
number of molecules
So,
mole of
gas contains
number of molecules
Therefore, the number of molecules present in nitrogen gas are,
What dont u understand about lewis dot structures???.
.how to determine the number of dots ..or
The answer is B.
You can rule C out because divergent means moving away. Rule out A because there is an oceanic and continental plate, not 2 of the same type. Rule D out for the same reason.
Answer:
His results will be skewed because there was more water than stock solution. Which would cause the percentage solution to be less than 50% therefore the density would be less than the actual value.
Explanation:
The solution will have percentage less than that of 50%. Therefore the density would be less than the actual value.
Suppose there should be 50 mL of the solution, and he added 60 mL. So 10 mL of the solution is added more.
Suppose the mass of the solute is m.
Originally, the density is =

Now after adding extra 10 mL , the density becomes
.
Therefore, 
So the density decreases when we add more solution.
Answer:
[Na₂CO₃] = 0.094M
Explanation:
Based on the reaction:
HCO₃⁻(aq) + H₂O(l) ↔ CO₃²⁻(aq) + H₃O⁺(aq)
It is possible to find pH using Henderson-Hasselbalch formula:
pH = pka + log₁₀ [A⁻] / [HA]
Where [A⁻] is concentration of conjugate base, [CO₃²⁻] = [Na₂CO₃] and [HA] is concentration of weak acid, [NaHCO₃] = 0.20M.
pH is desire pH and pKa (<em>10.00</em>) is -log pka = -log 4.7x10⁻¹¹ = <em>10.33</em>
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Replacing these values:
10.00 = 10.33 + log₁₀ [Na₂CO₃] / [0.20]
<em> [Na₂CO₃] = 0.094M</em>
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