Recent questions in Chemistry

Use the data to determine rate law for reaction: $2NO+H_2\rightarrow N_2O+H_2O$

asked Dec 18, 2013 by sreemathi.v

1 answer

In DNA, the complimentary bases are :

asked Dec 18, 2013 by thanvigandhi_1

0 answers

It take 40min for concentration of reactant in first order to drop from 0.4M to 0.3M at $25^oC$ .How long it will take for reaction to be 90% complete?

asked Dec 18, 2013 by sreemathi.v

1 answer

For chemical reaction shown below.Which of following statements can be rightly assumed?

asked Dec 18, 2013 by sreemathi.v

1 answer

Consider proposed mechanism for reaction between nitrogen monoxide and hydrogen gas.Step (i): $2NO\rightarrow N_2O_2$ ,Step 2: $N_2O_2+H_2\rightarrow N_2O+H_2O$ ,Step 3: $N_2O+H_2\rightarrow N_2+H_2O$ .If step 2 rate determining step,then rate law for reaction and all the intermediate of reaction will be

asked Dec 18, 2013 by sreemathi.v

1 answer

The half life of carbon is 5730years.Approximately how many years will it take for 94% of a sample to decay?

asked Dec 18, 2013 by sreemathi.v

1 answer

Which of these changes with time for $1^{st}$ order reaction $(i)\;\text{rate of reaction}\\(ii)\;\text{rate constant}\\(iii)\;\text{half life}\\(iv)\;\text{concentration of reactant}$

asked Dec 18, 2013 by sreemathi.v

1 answer

Rate of reaction increases by factor of 10 when temperature increased from $300K$ to 400K.Then find activation energy of reaction

asked Dec 18, 2013 by sreemathi.v

1 answer

The decomposition of hydrogen bromide into hydrogen and iodine is second order reaction.The reaction rate constant is $K=0.08Lmol^{-1}s^{-1}$ .How long it take an initial concentration of 0.04M to decrease to half this concentration?

asked Dec 18, 2013 by sreemathi.v

1 answer

At $150^oC$ the decomposition of acetaldehyde to methane is first order reaction. If rate constant for reaction at $750^oC$ is $0.05m^{-1}$ , how long does it take a concentration of $0.04\;mol\;L^{-1}$ of acetaldehyde to reduce concentration of $0.03\;mol\;L^{-1}$ ?

asked Dec 18, 2013 by sreemathi.v

1 answer

What is the rate constant for a reaction of $(CH_3)_3CBr$ with water is represented below : $CH_3)_3CBr+H_2O\rightarrow (CH_3)_3COH+HBr$ where the following data was obtained experimentally:

asked Dec 18, 2013 by sreemathi.v

1 answer

If a reactant is used up according to a first order rate equation and initial concentration of reactant is $32mol\;L^{-1}$ what is concentration of reactant after six half lives have passed?

asked Dec 18, 2013 by sreemathi.v

1 answer

Consider the following reaction:- <p> Step (i): $H_2O_2+I^-\rightarrow H_2O+IO^-$ , </p> <p> Step (ii): $H_2O_2+IO^-\rightarrow H_2O+O_2+I^-$ , </p> then reaction intermediate will be

asked Dec 18, 2013 by sreemathi.v

1 answer

Addition of catalyst to reaction increases the rate because it

asked Dec 18, 2013 by sreemathi.v

1 answer

Which one of following changes would result in greatest increase in reaction rate in the following two-step mechanism?

asked Dec 18, 2013 by sreemathi.v

1 answer

Consider following reactions :(i) $H_2(g)+I_2(g)\rightarrow 2HI(g),(ii)\;2Mg(s)+O_2(g)\rightarrow 2MgO(s),(iii)\;CaCO_3(s)+2H^+(aq)\rightarrow Ca^{+2}(aq)+H_2O(l)+CO_2(g)$ .When we increase surface area will increase reaction rate in

asked Dec 18, 2013 by sreemathi.v

1 answer

For following potential energy diagram : True statement is :-

asked Dec 18, 2013 by sreemathi.v

1 answer

The rates in order of fastest to slowest for this reaction: a 5g of powdered $Mg(s)+2HCl(aq)\rightarrow MgCl_2(aq)+H_2(g)$ are:

asked Dec 18, 2013 by sreemathi.v

1 answer