The reaction: (ch3)3cbr + oh− → (ch3)3coh + br− in a certain solvent is first order with respect to oh−. in several experiments, the rate constant k was determined at different temperatures. a plot of ln(k) vs 1/t was constructed and the slope of the line was -1.10 x 104 k with a y-intercept of 33.5. what is the value for k at a temperature of 25°c? a. 3.69 × 10-7 s-1 b. 3.51 s-1 c. 3.23 × 10-2 s-1 d. 1.10 × 104 s-1

C

Explanation:

This is the Arrehnius equation in lineal form, lnK = -Ea/RT + lnA.

so the slope corresponds to -Ea/R and the intercept is lnA. So from the slope we can calculate the Ea Ea=-(-1.10*10^4)*8.314=9.1*10^4 J/lol

A=e^(33.5)=3.53*10^14

Finally with these values and using the Arrehnius equation we can calculate K at 25°C.

k=Ae^-(Ea/RT)

k=(91.06)e^-(9.1*10^4/(8.314*298))

k=3.23*10^-2

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g

plants need sunlight, water, and carbon dioxide to make food. plants use the raw materials of water, nutrients they absorb from soil, and carbon dioxide to make sugars the plant can use. energy from the sun and chlorophyll are also needed.