Answer:
B. A precipitate will form since Q > Ksp for calcium oxalate
Explanation:
Ksp of CaC₂O₄ is:
CaC₂O₄(s) ⇄ Ca²⁺ + C₂O₄²⁻
Where Ksp is defined as the product of concentrations of Ca²⁺ and C₂O₄²⁻ in equilibrium:
Ksp = [Ca²⁺][C₂O₄²⁻] = 2.27x10⁻⁹
In the solution, the concentration of calcium ion is 3.5x10⁻⁴M and concentration of oxalate ion is 2.33x10⁻⁴M.
Replacing in Ksp formula:
[3.5x10⁻⁴M][2.33x10⁻⁴M] = 8.155x10⁻⁸. This value is reaction quotient, Q.
If Q is higher than Ksp, the ions will produce the precipitate CaC₂O₄ until [Ca²⁺][C₂O₄²⁻] = Ksp.
Thus, right answer is:
<em>B. A precipitate will form since Q > Ksp for calcium oxalate</em>
<em></em>
<u>Answer:</u> From the given gases, the greatest rate of effusion is of 
<u>Explanation:</u>
Rate of effusion of a gas is determined by a law known as Graham's Law.
This law states that the rate of effusion or diffusion of a gas is inversely proportional to the square root of the molar mass of the gas. The equation given by this law follows:
It is visible that molar mass is inversely related to rate of effusion. So, the gas having lowest molar mass will have the highest rate of effusion.
For the given gases:
Molar mass of 
Molar mass of 
Molar mass of 
Molar mass of 
Molar mass of 
The molar mass of methane gas is the lowest. Thus, it will have the greatest rate of effusion.
Hence, the greatest rate of effusion is of
Molecular weight calculation:
24.305 + (15.9994 + 1.00794)*2
Molar mass of Mg(OH)2 = 58.31968 g/mol
In scientific notation, a number is less than ten but more than one.
Move the decimal point from 0, 250.000 <- this is the same as 250 to between 2 and 5.
I had to move two spaces.
2.5^2
I hope this helps!
~kaikers
