Which set of materials includes the fewest number of ingredients that are needed to make a lemon into an effective battery that can power a digital clock?
O a lemon, copper wire, an external source of reactants, and copper and zinc electrodes
a lemon, a lime, copper electrodes, and an external source of reactants
a lemon, copper wire, and copper and zinc electrodes
a lemon, platinum electrodes, and copper wire

answer; i believe that the correct answer is (a) potassium(k)

option c: 1605.1 kj

the balanced chemical reaction for combustion of methane is as follows:

here, enthalpy formation of is -74.7 kj/mol, 0 kj/mol, -393.5 kj/mol and -241.82 kj/mol respectively.

the heat released or can be calculated as follow:

putting the values,

thus, heat released by combustion of 1 mol of methane is 802.54 kj/mol. thus, for 2 mol, heat released will be:

therefore, heat released by the combustion of 2 mol of methane is 1605.1 kj.

a) adding base pairs

c) unwinding the helix

there are possible two correct answers for this question.

dna polymerase doesn’t add base pairs, it adds single nucleotides which are complentar to coding strand . also dna polymerase can’t unwind the dna helix alone. dna helicase can do that, using energy derived from atp hydrolysis.

dna polymerase are enzymes that synthesize dna molecules from deoxyribonucleotides. these enzymes replicate the dna strand and create two identical dna strands from a single original dna molecule. some of dna polymerases have a function of correcting erros which are made during replication and this process is called proofreading. if the dna polymerase detects that incorrectly paired nucleotide has been added, it will remove and replace the wrong nucleotide.