Answer:
A
Explanation:
Hot air is less dense therefore it rises. Cold air is more closely packed therefore it is more dense. Less dense things rise while more dense things sink.
Answer:
Exothermic reaction: In exothermic reaction, energy is transferred to the surroundings, and the surrounding temperature increases, this is known as exothermic reaction. In other words energy exits in exothermic reaction. Some example of exothermic reactions are:
1) Neutralisation reaction.
2) Combustion reaction.
3) Some oxidation reaction.
Endothermic reaction: In endothermic reaction, energy is taken in from the surrounding, and the surrounding temperature decreases, this is known as endothermic reaction. In other words energy enters in endothermic reaction. Some example of exothermic reactions are:
1) Thermal decomposition.
2) Reaction between citric acid and sodium hydrogen carbonate.
Answer:
True
Explanation:
Hydrogen has three naturally occuring isotopes and copper has two.
Answer:
D
Explanation:
Glucose is produced through a process powered by sunlight that consumes Carbon Dioxide and produces oxygen as a waste product. In order for glucose to be produced, Carbon dioxide (a compound) must be, in essence, converted into a completely different chemical: dioxygen.
