Energy Changes in Chemical Reactions

Give the balanced chemical equation for the burning of natural gas.

Write any two disadvantages of dams.

Define energy density.

When ammonium chloride is mixed with barium hydroxide in a beaker, it becomes cold.

Which of the following is not an exothermic change?

Energy of products is always lower than the energy of reactants as they are more stable.

Combustion reaction is a type of exothermic reaction.

Heat is released in an endothermic reaction.

In which of the following reaction, heat is liberated?

Ask your mother which fuel does she use in the kitchen? Is it a renewable or non-renewable resource? What steps does she take to save fuel?

After rise in temperature, the activation energy will:

What are the different purposes for which fuels such as petrol, diesel, kerosene, natural gas, coal and wood are used?

 The energy of activation for reaction ${\mathrm{N}}_2\left(\mathrm{g}\right)+3{\mathrm{H}}_2\left(\mathrm{g}\right)\mathrm{ }\to \mathrm{ }2\mathrm{N}{\mathrm{H}}_3\left(\mathrm{g}\right)+22\mathrm{ }\mathrm{k}\mathrm{c}\mathrm{a}\mathrm{l}$  is $70\mathrm{ }\mathrm{k}\mathrm{c}\mathrm{a}\mathrm{l}$. What will be the activation energy for
$2{\mathrm{N}\mathrm{H}}_3\left(\mathrm{g}\right)\to \mathrm{ }{\mathrm{N}}_2\left(\mathrm{g}\right)+3{\mathrm{H}}_2\left(\mathrm{g}\right)$ 

The chemical reactions in which the reactants require high amount of activation energy are generally

Name the gas added to air by:

Respiration

Give an example of an endothermic reaction.

Look at the pictures given below. Do you find any difference? Tell the differences. 

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The activation energy in a chemical reaction is defined as

A certain reaction rate increases $1000$ folds in the presence of a catalyst at $27°\mathrm{C}$ . The activation energy of the original pathway is $98 \mathrm{kJ} {\mathrm{mol}}^{-1}$. What is the activation energy of the new pathway?

Energy of activation is lowest for which reaction?