Chemistry Answers

Given that at body temperature, Kw = 10^-13.6, what is the pH of neutral water at body temperature? 

The volume of gastric fluid in your stomach is 100 cm3 and its pH = 2. Calculate the number of H+ ions in your stomach. You need to know that Avogadro’s Number, NA, is 6.02*1023 mol^-1. 

A catalyst (e.gg an enzyme) speeds up a reaction by changing (tick one or more of these options): 

a) the heat of reaction 

b) the energy of activation 

c) the frequency of collisions of reactant molecules 

d) the frequency of successful collisions

Which of the following solutions (of similar concentration) contains the weakest base? 

Their pH values are as follow: 

a) 6.00 

b) 7.00 

c) 13.00 

d) 8.00

The delta H for reaction (4) is negative. Could you increase the yield of glucose 6-phosphate by 

a) increasing the temperature 

b) decreasing the temperature 

c) adding a catalyst 

Glucose-1-phosphate (G1P) is converted into glucose-6-phosphate (G6P) by the enzyme phosphoglucomutase according to the equation: 

Glucose-1-phosphate ⇋ Glucose-6-phosphate

At equilibrium, [G1P] = 3.0*10^-3 mol L^-1 and [G6P] = 5.8*10^-2 mol L^-1. What is the value of the equilibrium constant? 

Glucose-1-phosphate (G1P) is converted into glucose-6-phosphate (G6P) by the enzyme phosphoglucomutase according to the equation: 

Glucose-1-phosphate ⇋ Glucose-6-phosphate

At equilibrium, [G1P] = 3.0*10^-3 mol L^-1 and [G6P] = 5.8*10^-2 mol L^-1. What is the value of the equilibrium constant? 

Ethanol trapped in a gel is a common camping fuel. The thermochemical equation for the combustion of ethanol is : 

C2H5OH (l) + 3O2(g) → 2CO2(g) + 3H2O(g)

The ΔH for reaction (3) is -1368 kJ mol-1. What mass of ethanol must be burned to supply 350 kJ of heat? 

Calculate the number of N atoms in 33.0 mg of NH₄NO₂.

Acidic strength order of dinitrobenzoic acids having (2,6), (2,3), (2,4) and (3,4) positions