Energy can be conserved by efficient energy use.
Answer: Option A
<u>Explanation:</u>
Energy can be transferred from one form to another, but it cannot be destroyed or created. So it can be conserved if efficiently used. Thus efficient usage of energy lead to conservation of energy. Due to conservation of energy, the forces can be renewable and non-renewable.
So, we should know how the input energy can be completely converted to another form of energy leading to efficient usage of energy without any loss. As if there is no loss, input energy will be equal to output energy leading to 100% efficiency.
45 g Thirty grams of lead oxide and fifteen grams of ammonia react completely to produce solid lead, nitrogen gas, and liquid water.
Answer: 0.714 moles of 
will be produced from 237.1 g of potassium iodide
Explanation:
To calculate the moles :
The balanced chemical reaction is:
According to stoichiometry :
2 moles of 
produce = 1 mole of
Thus moles of will require=
of
Thus 0.714 moles of will be produced from 237.1 g of potassium iodide
You have a. 3, b. 2, e. 6, f. 3, i. 1
The balance chemical reaction describing the reaction between Mg2+ and Cl- is shown below,
Mg2+ + 2Cl- ----> MgCl2
This is a reaction where there is a transfer of electrons. Since the valence electron of Mg2+ is 2 and that of Cl- is only 1. There is a need for 2 Cl- to react with 1 Mg2+ in order to balance the equation.
Thus, the anwer is MgCl2.
