Answer:
See explanation
Explanation:
A reaction in which heat and light are produced is a combustion reaction. Combustion is said to have occurred when a substance is burnt in oxygen.
The balanced equation of the reaction is;
4Li(s) + O2(g) ------->2Li2O(s)
This reaction is exothermic because heat was produced. The reaction has a low activation energy as the metal easily burst into flames in oxygen. A catalyst is not needed in this reaction because it has a low activation energy.
According to the law of conservation of mass. Atoms are neither created nor destroyed in a chemical reaction. What this means is that in a chemical reaction, the number of atoms of each element on the left hand side must be the same as the same as the number of atoms of the same element on the right hand side.
Answer:
The most acidic solution had a pH of 3.27.
Explanation:
In order to solve this problem we need to keep in mind that the lower the pH of a solution is, the more acidic the solution is.
If among the pH readings across the measured breakfast drinks, the lowest one was 3.27 (as the problem tells us with the range), then that drink was the most acidic one.
Conversely, the least acidic one had a pH of 3.88.
Explanation:
The given reaction is redox reaction but not combustion reaction.
Redox reaction : It is a chemical reaction in which oxidation and reduction occurs simultaneously.Oxidation is gaining of electrons and reduction is loosing of electrons.
oxidation
reduction
Potassium when reacts with water ,gives potassium ion in aqueous medium and combines with hydroxide ion present in water to form potassium hydroxide where as 
ions of water by gaining electrons (from potassium in water) gives hydrogen gas.
Hence , yes it is a redox reaction
Combustion reaction are the chemical reaction in which one reactant react with oxygen molecule to give heat and light.
Here in given reaction no oxygen molecule is appearing on reactant side.
Hence not a combustion reaction.
Answer:
C. Adding a catalyst
Explanation:
Because the catalyst increases the rate of chemical reaction
