Answer:
The independent variable (IV) is the characteristic of a psychology experiment that is manipulated or changed by researchers, not by other variables in the experiment.
For example, in an experiment about the effect of nutrients on crop growth: The independent variable is the amount of nutrients added to the crop field. The dependent variable is the biomass of the crops at harvest time.
Therefore : 3. the variable that responds to what the scientist changes in an experiment
It is most influenced by maritime tropical
First, we need the balanced equation: H₂ + Cl₂ ---> 2HCl
since not much information is given, I am assuming we are at STP and that 22.4 Liters= 1 mol
1) let's convert the volume to moles using the molar volume of a gas. also we need to convert the cm₃ to mL, then to Liters.
8 cm³ (1 ml/ 1 cm³)(1 L/ 1000 mL) (1 mol/ 22.4 Liters)= 3.6x10⁻⁴ moles of H₂
2) let's use the mole ratio of the balanced equation to convert moles of H₂ to moles of HCl
3.6x10⁻⁴ mol H₂ (2 mol HCl/ 1 mol H₂)= 7.1x10⁻⁴ mol HCl
3) lastly, we convert the moles of HCl to grams using the molar mass.
molar mass of HCl= 1.01 + 35.5= 36.51 g/mol
7.1x10⁻⁴ mol HCl (36.51 g/mol)=<span> 0.026 grams HCl</span>
Answer:
The charge would be +1
Explanation:
Protons have a positive charge while electrons have a negative charge. Therefore, it's simple subtraction. In every case, subtract the number of electrons from the number of protons.
13 - 12 = 1
Therefore the charge is +1
Here's one more example:
If the element chromium (Cr) has 24 protons and 28 electrons, what is its charge? Remember that protons have a positive charge and electrons have a negative charge.
24 - 28 = -4
Charge = -4
It would be written as followed when associating charge with a specific element: 
If an element has a neutral charge, that means the number of protons and neutrons are the same. If you look at the periodic table of elements, all of the elements listed have a neutral charge. The 0 isn't showed in the corner because it isn't necessary.
Bonus Information:
This isn't related to your question, but I've come across confusions when it comes to particles. Remember that protons (+) and electrons (-) are the only particles that have a charge, therefore, as it says in it's name, neutrons are neutral or have no charge. Neutrons do not contribute to charge, but they do contribute to the <em>mass</em> of an atom. So the number of protons added to the number of neutrons equate to the mass of an atom. Electrons have mass, but it's so miniscule and insignificant that it doesn't even contribute to the overall mass of the atom, so don't count those.
Remember:
C = p - e
M = p + n
C = atomic charge, M = atomic mass, p =protons, n = neutrons, e = electrons
I hope this helps!