Answer is: a) is has increased.
There are two types of reaction:
1) endothermic reaction (chemical reaction that absorbs more energy than it releases).
For example, the breakdown of ozone is an endothermic process. Ozone has lower energy than molecular oxygen (O₂) and oxygen atom, so ozone need energy to break bond between oxygen atoms.
2) exothermic reaction (chemical reaction that releases more energy than it absorbs).
For example, ΔH(reaction) = -225 kJ/mol; this is exothermic reaction.
Answer:
convection
Explanation:
as air is heated, it rises up and away from the heat source, cools then falls closer to the heat source over and over again.
Question:
How could you use a model to show the cause-and-effect relationship between Earth's rotation and the apparent motion of the stars across the night sky?
Answer:
Gravity? or density because of the pull from the sun.
Alka-seltzer in an antacid that contains a mixture of sodium bicarbonate and citric acid. When the tablet is dissolved in water, the reactants which are in solid form in tablet become aqueous and react with each other.
During this reaction, Carbon Dioxide gas is evolved which causes the reaction mixture to fizz. The equation is given below.

Rate of the above reaction is affected by the Temperature.
As the temperature increases , the rate of the reaction increases. This happens because at higher temperature, the collisions between reacting species are more which result in formation of product in less time. This increases the rate of reaction.
We have been given equal volumes of water for each beaker. But the temperature of beaker c is 80°C which is the highest temperature. That means the reaction in beaker c is fastest.
Whereas beaker a is at lowest temperature (30°C) , therefore the reaction in beaker a would be slowest .
Therefore the answer that correctly orders the reaction rates from fastest to slowest reaction is beaker c > beaker b > beaker a