What overall effect does adding a catalyst have on a chemical reaction?
it slows the reaction.
it speeds up the reaction.
it reduces the concentration of products.
it increases the concentration of reactants.

Option (b) is the correct answer.

Explanation:

Catalyst are the species or substance which increases the rate of a reaction without itself getting consumed in the chemical reaction.

A catalyst changes the path of a reaction so that the reactant molecules with less energy can easily participate in the reaction. Therefore, the formation of products become faster.

Thus, we can conclude that overall effect of adding a catalyst have on a chemical reaction is that it speeds up the reaction.

explanation:

metals have excess of electrons whereas non-metals have deficiency of electrons. thus, in order to gain stability metals easily donate their electrons to the non-metals.

for example, electronic configuration of sodium is and electronic configuration of phosphorous is .

when a phosphorous atom and sodium atom combine together then sodium will donate is extra one electron to the phosphorous atom. as a result there will be formation of ionic bond between sodium and phosphorous.

the reaction will be as follows.

there, are three sodium sodium atoms and each of them will donate its one extra electron to phosphorous atom. thus, the sub-shell of phosphorous gets completely filled.  

thus, we can conclude that electrons are transferred from atoms of sodium to atoms of phosphorous. this transfer makes the sodium atoms donate one electron and the phosphorous atoms to gain one electron. as a result, the sodium and phosphorus atoms strongly attract each other.

both adhesion and cohesion are attractions.

they are different in that adhesion is the force of attraction between the molecules of two different substances, whereas cohesion is the force of attraction between molecules of the same substance.

possible examples include capillary action, in which the adhesion between water and glass causes the water to rise in a narrow tube against the force of gravity.

because of hydrogen bonding, water is extremely cohesive.

this causes molecules on the surface of water to be drawn inward, which is why drops of water form beads on smooth surfaces.

hope this .