General Chemistry Answers

The equilibrium constant, K_c, for the following reaction is 1.29×10^-2 at 600 K.

COCl₂(g) CO(g) + Cl₂(g)

Calculate the equilibrium concentrations of reactant and products when 0.351 moles of COCl₂(g) are introduced into a 1.00 L vessel at 600 K.

[COCl₂]=  M

[CO]=  M

[Cl₂]=  M

a farm worker is exposed to trifluralin, a commonly used pesticides while working in the fields. Calculate the risk of the worker exposed to 0.01mg/m³ who works 8 hours per day, 7 weeks, for 4 months a year, and for 25 years. Assume a body weight of 70kg and an inhalation volume of 20m³ per 8 hours. The slope factor for Trifluralin is 8.4*10^-1 (mh/kg.day)^-1

Describe how to prepare 250 cm3 of sodium carbonate solution at a concentration of 0.5 mol dm-3 supplied Na2CO3, 10HO crystals.

The equilibrium constant for the production of ammonia, used as fertilizer, is 3.65x 10

8 at 25 ⁰C. N2(g) + 3 H2(g) ⇋ 2 NH3(g) . Calculate the equilibrium concentration of hydrogen gas, if at

equilibrium the concentrations of nitrogen and ammonia are 2.56 M and 5.76 M

The method for removing toxins in cycad fruit that was used by the Aboriginal

and Torres Strait Islander Peoples was:

A) Burning the plant to ashes

B) Crushing the cycad into a powder

C) Roasting, crushing and then soaking in a bowl of water

D) Roasting, crushing and then leaching in a flowing river

Which of the following best describes the effect of a catalyst on the

equilibrium constant K and the rate of reaction?

A) Reaction rate increases in the forward direction and K increases

B) Reaction rate decreases in the reverse direction and K decreases

C) Reaction rate increases in both directions and K remains constant

D) Reaction rate decreases in both directions and K increases

Which of the following combinations forms a precipitate?

A) BaNO3(aq) + NH4OH(aq)

B) Mg(NO3)2(aq) + NaCl(aq)

C) CH3COOK(aq) + NaNO3(aq)

D) BaNO3(aq) + Na2SO4(aq)

( which is the correct answer )

For the reaction:

H2(g) + Br2(g) ⇌ 2HBr(g)

Which of the following best describes the effect of increased pressure on the

equilibrium constant K and rate of reaction?

A) Reaction rate increases in the forward direction and K increases

B) Reaction rate decreases in the forward direction and K decreases

C) Reaction rate increases in both directions and K remains constant

D) Reaction rate decreases in both directions and K increases

An equilibrium exists between NO2 and N2O4 in a gaseous system as

represented below:

2NO2(g) ⇌ N2O4(g)

NO2 (g) has an intense orange appearance whereas N2O4 (g) is colourless.

Heating this system at equilibrium increases the intensity of the orange colour.

From this information, the forward reaction would be classified as:

A) endothermic

B) exothermic

C) both exothermic and endothermic

D) neither exothermic nor endothermic

For the reaction in question (6), the value of the equilibrium constant

at 300K compared with that at 500K is:

A) Larger

B) The same

C) Smaller

D) Insufficient information for a comparison to be made