D. Theories
Scientific theories are the best explanations so far to explain a pattern seen in nature.
Answer:1176
Explanation:
Number of male students: 2940*(60/100)=1764
So the number of female students would be:
2940-1764=1176
Answer:
The answer to your question is 1 M
Explanation:
Data
Molarity = ?
mass of CaCl₂ = 222.2 g
Volume = 2 l
Process
1.- Calculate the molar mass of CaCl₂
CaCl₂ = 40 + (35.5 x 2) = 40 + 71 = 111 g
2.- Calculate the moles of CaCl₂
111g of CaCl₂ ---------------- 1 mol
222.2 f of CaCl₂ ---------------- x
x = (222.2 x 1) / 111
x = 222.2 / 111
x = 2 moles
3.- Calculate the Molarity
Molarity = moles / Volume
-Substitution
Molarity = 2/2
-Result
Molarity = 1
Answer:
a. The reaction is endothermic.
Explanation:
The heat involved in a chemical reaction is given by the enthalpy change (ΔH), which is equal to the balance between the chemical bonds that are broken (release energy) and the chemical bonds that are formed (need energy):
ΔH ≅ bonds broken - bonds formed
If broken bonds > bonds formed ⇒ ΔH > 0 ⇒ endothermic reaction
Therefore, the reaction is endothermic (it requires energy).
