To solve the problem, we need to determine the net effect of a price increase followed by a discount, both expressed in percentages.
- Price Increase: An upward change in price, expressed as a percentage of the original price.
- Discount: A reduction applied after the increase, on the increased price.
- Net Change Formula: When an increase of x% is followed by a decrease of y%, the net percentage change is given by:
\[ \text{Net \% change} = x - y - \frac{xy}{100} \]
- Increase = 25%
- Discount = 20%
\[ \text{Net \% change} = 25 - 20 - \frac{25 \times 20}{100} = 5 - 5 = 0\% \]
There is no net change in the price; the overall percentage change is 0%.
The speed at which a chemical reaction takes place is called the rate of reaction. The rate of reaction depends on various factors like concentration of the reactants, temperature, etc. The relation between the rate of reaction and the concentration of reacting species is represented by the equation \( r = k[A]^x[B]^y \), where \( x \) and \( y \) are the order of the reaction with respect to the reactants A and B, respectively. The overall order of the reaction is \( x + y \). The rate of reaction can also be increased by the use of a catalyst which provides an alternate pathway of lower activation energy. It increases the rate of forward and backward reactions to an equal extent. It does not alter the Gibbs energy of the reaction.