Answer:
Ca^2+
Explanation:
As we know, more energy is required to remove an electron from a positively charged ion than is required to remove an electron from a neutral atom. Hence, the second ionization energy of calcium is greater than its first ionization energy.
However, the third and fourth ionization energies of calcium are much higher than the second ionization energy because they involve removal of electrons from an inner filed shell. This process requires a lot of energy and is often not feasible.
Hence, the most common ion of calcium must be Ca^2+ where only two electrons are removed from calcium.
Answer:
40.0 L.
Explanation:
- We can use the general law of ideal gas: <em>PV = nRT.</em>
where, P is the pressure of the gas in atm.
V is the volume of the gas in L.
n is the no. of moles of the gas in mol.
R is the general gas constant,
T is the temperature of the gas in K.
- If P and T are constant, and have different values of n and V:
<em>(V₁n₂) = (V₂n₁).</em>
V₁ = 50.0 L, n₁ = 2.0 moles,
V₂ = ??? L, n₂ = 2.0 mol - 0.4 mol = 1.6 mol.
∴ V₂ = (V₁n₂)/(n₁) = (50.0 L)(1.6 mol)/(2.0 mol) = 40.0 L.
H2O is A chemical reaction of the most oxygen atoms
To convert grams to moles, we need the molar mass of the element or compound. remember you can determine the molar mass of a molecule by adding the atomic mass of each atom from the periodic table.
molar mass of Na= 23.0 g/ mol
130 g (1 mol Na/ 23.0 grams)= 5.65 moles or 6 moles.
