What change would you expect on the rate of the SN2 reaction of 1-iodo-2-methylbutane with cyanide ion if the nucleophile concentration is halved and the alkyl halide concentration is doubled? a. divided by 4
b. halved
c. no effect
d. increased 2x
e. increased 3x
f. increased 6x
g. increased 9x

no effect

Explanation:

In an SN2 reaction, the mechanism is bi-molecular and first order in both the alkyl halide and the nucleophile.

Hence the rate of reaction is;

Rate = k [1-iodo-2-methylbutane] [cyanide ion]

Given that it is a bimolecular reaction, if we double the concentration of 1-iodo-2-methylbutane and the concentration of the cyanide ion is halved, the rate of reaction remains the same.

a mercury barometer is a device that uses the physical properties of mercury in a tube to measure barometric pressure. mercury barometers are used for : -

1. measurement of atmospheric pressure  

2. determining the altitude of a place

3. weather forecasting

4. calibration and checking of aneroid barometers

5. application in fluid mechanics

6. measurement of pressure in aircrafts

7. surface weather analysis

8. preparation of barographs

9. usage in physical sciences like physics, astronomy & chemistry

10. preparation of aircraft altimeters

characteristics of mercury barometer : -

1.used to define and measure atmospheric pressure.

2.on the average at sea level the column of mercury rises to a height of about 760 mm.

3.this quantity is equal to 1 atmosphere.

4.it is also known as standard atmospheric pressure.

5.a barometer in which the weight of a column of mercury in a glass tube with a sealed top is balanced against that of the atmosphere pressing on an exposed cistern of mercury at the base of the mercury column, the height of the column varying with atmospheric pressure.