A student wants to study the effect of sunlight on plant growth. In his experment, 12 plants
receive normal amounts of sunlght, but half of
them are kept under bight sun lamps all night long. After 6 weeks, the plants heights are measured. what are the Independent and dependent variables? What is the experimental group? What is the control group?

Independent variable: AMOUNT OF SUNLIGHT

Dependent variable: HEIGHT OF PLANTS

Experimental group: PLANTS KEPT UNDER BRIGHT SUN LAMPS ALL NIGHT

Control group: PLANTS THAT RECEIVED NORMAL AMOUNT OF SUNLIGHT

Explanation:

Independent variable refers to the variable that is manipulated or changed in an experiment in order to effect a measurable response. In this case, the independent variable is the VARYING AMOUNT OF SUNLIGHT.

Dependent variable is the variable that the experimenter measures or the variable that responds to changes made to independent variable. The dependent variable in this case is the HEIGHT OF PLANTS measured.

Experimental group is the group in an experiment that receives the experimental treatment. In this case, the PLANTS KEPT UNDER BRIGHT SUN LAMPS ALL NIGHT is the experimental group.

Control group is the group that does not receive any experimental treatment/independent variable. In this case, the PLANTS THAT RECEIVED NORMAL AMOUNT OF SUNLIGHT is the control group.

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !

that's what i got you can count the number of atoms