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What is Hund's rule?

Electrons occupy every orbital in each subshell once and then occupy the full orbital with both electrons 

IN
Answered by Intesar N. Chemistry tutor
2912 Views

What does the DNA sequence being 'degenerate' mean?

Amino acids are coded for by specific codons. There are some instances where some particular amino acids can be coded for by more than one codon (codon being three nucleotides bonded together). This is kn...

BN
Answered by Bibi N. Biology tutor
11386 Views

f(x) = 2x^3 – 7x^2 + 4x + 4 (a) Use the factor theorem to show that (x – 2) is a factor of f(x). (2) (b) Factorise f(x) completely.

We are presented with a third order polynomial with 4 terms, so we expect 3 solutions for f(x)=0. To prove that (x-2) is a factor we must insert the value of x=2 into the function and if f(2)=0 then we ha...

NA
Answered by Nazar A. Maths tutor
15522 Views

Describe and explain the effects of pH, temperature, enzyme concentration and substrate concentration on enzyme activity

pH: All enzymes have an optimum pH value which is very specific. This is because hydrogen ions and hydroxide ions have very significant changes on the tertiary structure of an enzyme, whi...

EO
Answered by Eloise O. Biology tutor
15850 Views

Putting bee honey on a cut kills bacteria. Honey contains a high concentration of sugar. Use your knowledge of water potential to suggest how putting honey on a cut kills bacteria.

Once honey is added to an infected cut, the osmotic gradient favours water moving from the bacterial cells to the honey. This is because the water potential is lower in the honey. As a result of the loss ...

HM
Answered by Harry M. Biology tutor
3571 Views

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