What is true of enzymes? they only speed up reactions. they speed up or slow down any reaction in a living thing. they act as catalysts, each for one specific reaction. they only slow down reactions

There are 2 correct options for this problem.

1) They only speed up the chemical reactions. : True

Enzymes are biological catalysts. A catalyst lowers the activation energy of the reaction. When a reaction needs less energy to start, it occurs at a faster rate.

Many biological reactions that occur in our body are occurring at body temperature. The reactions would become very slow at this temperature . Therefore enzymes act a catalyst to speed up these reactions.

2) They act as catalysts, each for one specific reaction. : True

This option is true because as discussed above, enzymes are catalyst and their job is to speed up a chemical reaction. Enzymes have active sites where a particular substrate can bind during the reaction. Therefore a given enzyme acts a catalyst for a specific reaction only.

answer: enthalpy

explanation:

for a exothermic reaction, the energy is released i.e. the energy of the products is lower than the energy of the reactants.

= enthaply

= energy of products

= energy of reactants

as , thus comes out to be negative. negative value of enthalpy shows that the reaction is exothermic.

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.