Answer:
Adenine forms two hydrogen bonds with thymine;
guanine forms three hydrogen bonds with cytosine
Explanation:
There are three hydrogen bonds between guanine and cytosine. Between adenine and thymine, two hydrogen bonds form. Complementary pairs always include one base of purine and one base of pyrimidine.
Answer:
Metamorphic rock
Explanation:
metamorphic rocks do not get hot enough to melt they just get denser if they did they would become igneous rocks.
Mass percentage of a solution is the amount of solute present in 100 g of the solution.
Given data:
Mass of solute H2SO4 = 571.3 g
Volume of the solution = 1 lit = 1000 ml
Density of solution = 1.329 g/cm3 = 1.329 g/ml
Calculations:
Mass of the given volume of solution = 1.329 g * 1000 ml/1 ml = 1329 g
Therefore we have:
571.3 g of H2SO4 in 1329 g of the solution
Hence, the amount of H2SO4 in 100 g of solution= 571.3 *100/1329 = 42.987
Mass percentage of H2SO4 (%w/w) is 42.99 %
write the equation for the reaction
that is 6 F2 +P4 =4 PF3
find the theoretical mass that is
let the theoretical yield be represented by y
theoretical yield = 78.1/100 = 120/y
y= 153.6 grams
find the number of moles of PF3
moles = mass/molar mass
= 153.6/87.97 =1.746 moles
by use of mole ratio between F2 :PF3 which is 6:4 the moles of F2 is therefore= 1.746 x 6/4 = 2.62 moles
mass = moles x molar mass
= 1.746 moles x38 g/mol = 99.6 grams
