Answer:
-6.4x10⁻¹⁹ C
Explanation:
The elementary charge of one electron is -1.60x10⁻¹⁹C, so each electron has its charge, and a sample with more than one electrons will have a multiple of its charge, which is proportional to the number of electrons. So, if the oil droplet had 4 electrons, thus the charge will be four times the elementary charge:
4*(-1.60x10⁻¹⁹) C = -6.4x10⁻¹⁹ C
Answer:
3
Explanation:
On the left side we have 3 Calcium atoms and 6 fluorine atoms
that means there need to be the same number on the right side
in the CaF2 molecules we already have 2 fluorine atoms so by multiplying with 3 we get 3 Ca and 6F
You must add 45 mL of the 80 % alcohol to the 30 % alcohol to get a 35 % solution.
You can use a modified dilution formula to calculate the volume of 80 % alcohol
V1×C1 + V2×C2 = V3×C3
Let the volume of 80 % mixture 1 = <em>x</em> mL. Then the volume of the final 35 % mixture 3 = (405 + <em>x</em> ) mL
(<em>x</em> mL×80 % alc) + (405 mL×30 % alc) = (405 + <em>x</em>)mL × 35 % alc
80x + 12 150 = 14 175 + 35 x
45x = 2025
x = 2025/45 = 45