C. Sliding friction between a desk and the floor once it is moving
The effect of a catalyst is to increase the speed of the reaction, this is the speed at which reactants, A and B, are consumed, ant the product, C, is produced.
Given that when C is produced the solution bubbles, the bubbles are an indication of progression of the reaction.
The greater the speed of reaction, the earlier the reaction will end and the earlier the bubbles will stop.
So the student can identify the catalyst because the bubbles will stop first.
Answer: <span>The test tube that stops bubbling first contains the catalyst.</span>
Sperm cells inside the pollen grain travel down the pollen tube and into the ovary which contains the ovules. Fertilization occurs when one of the sperm cells fuses with the egg inside of an ovule
Answer: solar power
Explanation: Wind power is considered indirect forms of solar power because the wind's energy originates in the uneven heating of the Earth. Water power is considered indirect solar energy because water is evaporated by solar hear, lifted and carried by the winds
