<span>Answer:
K because it is metal and typically forms ionic bonds. Ar is also unlikely to form any bonds because it has a full outer shell of electrons, but it can form covalent bonds.</span>
The % yield of Ca(OH)₂ : 62.98%
<h3>Further eplanation
</h3>
Percent yield is the compare of the amount of product obtained from a reaction with the amount you calculated
General formula:
Percent yield = (Actual yield / theoretical yield )x 100%
An actual yield is the amount of product actually produced by the reaction. A theoretical yield is the amount of product that you calculate from the reaction equation according to the product and reactant coefficients
Reaction
CaO + H₂O ⇒ Ca(OH)₂
mass CaO= 4.2 g
mol CaO(MW=56,0774 g/mol) :

mol Ca(OH)₂ based on mol CaO
mol ratio CaO : Ca(OH)₂,= 1 : 1, so mol Ca(OH)₂ = 0.075
mass Ca(OH)₂(MW=74,093 g/mol) ⇒ theoretical

% yield :

Explanation:
The given data is as follows.
= 10 mM =
M
= 750 ml,
= 5 ml
= ?
Therefore, calculate the molarity of given NaCl stock as follows.


= 1.5 M
Thus, we can conclude that molarity of given NaCl stock is 1.5 M.
The answer is: 27 grams of aluminium.
Balanced chemical reaction: 2Al + 3H₂SO₄ → Al₂(SO₄)₃ + 3H₂.
n(H₂) = 1.5 mol; amount of hydrogen.
Form chemical reaction: n(Al) : n(H₂) = 2 : 3.
n(Al) = 2 · 1.5 mol ÷ 3.
n(Al) = 1.0 mol; amount of aluminium.
m(Al) = n(Al) · M(Al).
m(Al) = 1 mol · 27 g/mol.
m(Al) = 27 g; mass of aluminium.
Answer:
0.41 moles.
Explanation:
Given that:
Mass of helium = 4.00 g
Initial Volume = 24.4 L
initial Temperature = 25.0 °C =( 25 + 273) = 298 K
initial Pressure = 1.00 atm
The volume was reduced to :
i.e
final volume of the helium - 10.4 L
Change in ΔV = 24.4 - 10.4 = 10.0 L
Temperature and pressure remains constant.
The new quantity of gas can be calculated by using the ideal gas equation.
PV = nRT
n = 
n = 
n = 0.4089 moles
n = 0.41 moles.