Answer:
Once living organisms.
Explanation:
Living organisms take a <em>very </em>long time to turn into fossil fuels, so it's not the first option.
Waste from living organisms is called "bio-fuel", not fossil fuel, so second option is wrong.
Ancient rocks are not fuel, so 3rd option is incorrect.
Hope this helps!
Answer: The reaction is exothermic. The value of q is -542 kJ.
Explanation:
Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and for the reaction comes out to be positive.
Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and for the reaction comes out to be negative.
Thus 
evolves heat , it is exothermic in nature. The value of q is -542kJ.
The resource that the scientist is most likely working with is ores. Copper is typically extracted from its ore using different methods that highly depend on the nature and composition of the ore. Examples of copper ores are sulphide, silicate, carbonate, and sulphate ores. Copper extracted from these ores still undergo further processing and purification.
Answer:
yes it is balanced.
Explanation:
when you are balancing an equation you look at the elements or compounds on the reactants and product side, which must have the same number of elements on both sides. like the question above;
2 potassium on the reactant and product side.
2 chlorine on the reactant and product side.
6 oxygen on the reactant and product side.
Answer: 20
Explanation: there you go my freind
