Answer:
True
Explanation:
They are built from particles and blobs of congealed lava ejected from a single vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as cinders around the vent to form a circular or oval cone, making them the simplest out there
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.
Answer:
The limiting reactant is propene,
.
Explanation:

Moles of nitrogen propene = 2 mol
Moles of oxygen = 10 mol
According to reaction, 2 moles of propene reacts with 9 moles of oxygen gas, then 2 moles of propene will react with:

According to the question, we have 10 moles of oxygen gas, which is more than 9 moles of oxygen gas. This indicates that propene is present in a limiting amount hence, it is a limiting reactant.
The limiting reactant is propene, hence the correct answer is the
.