I believe the correct answer from the choices listed above is option A. It is a catalyst that <span> increases the rate of a chemical reaction. It provides another pathway for the reaction in order for it to hasten the speed of the reaction. Hope this answers the question. </span>
Answer:
The atom with the smallest mass is the hydrogen atom; its mass is about 10-27 kg. The masses of other atoms go up to about 200 times this. The nucleus of an atom is about 10-15 m in size; this means it is about 10-5 (or 1/100,000) of the size of the whole atom.
Answer:
meter
Explanation:
according si system meter is the correct unit for length
Answer: the color of light shining on the photocell.
Explanation:
1) In an experiment there are two kind of variables: independent variables and dependent variables.
2) The independent variable is the one that can be changed or manipulated. This is done because you want to learn how the changes in this variable may explain or are related to other variable (the dependent variable).
In the description of the experiment, the color of the light is being changed, by placing different color of cellophanes ove the same flashlight.
This is how, keeping the control over other possible variables (the flashlight kind and its distance from the photocell, for example) the experimenter manages to change one only variable: the color of light.
3) On the other hand, the dependent variable, is the variable that is being explained. You do not manipulate the dependent variable directly but you want to learn to what extent this dependent variable is determined by, explained by, predicted by, or simply related to, the independent variable.
In conclusion, the independent variable is the color of light.
