Answer:
a) There are
electrons in a liter of water.
b) The net charge is -53601707,1 C
Explanation:
a) To find out how many electrons are in a liter of water (equivalent to 1000 grams of water), we have to find out how many molecules of water there are and then multiply it by 10 (e- per molecule).
We can find out how many molecules are by finding the number of moles and then multiplying it by Avogadro's number (number of elements per mol):

b) As all electrons have the same charge, in order to find the net charge of those electrons we have to multiply the charge of a single electron by the number of electrons:

An important clarification is that while the net charge may seem huge, water as a whole is a neutral medium, because there are as many protons as there are electrons, and as they have the same charge, the net charge of water is 0.
Answer:
The two general types of air pollution are _____ and _____.
answer: gases and particles
Please Mark me as brainiest and follow
To find momentum you multiply the mass and velocity.
91 × 7 = 637 kg-m/s
Answer:
0.25 gram of neptunium is remaining
Explanation:
First we calculate the no. of half lives passed. For that we have formula:
n = t/T
where,
n = no. of half lives passed = ?
t = total time passed = 8 days (From Monday noon to Tuesday noon of following week)
T = Half Life Period = 2 days
Therefore,
n = 8 days/2 days
n = 4
Now, for the remaining mass of neptunium, we use the formula:
m = (mi)/(2)^n
where,
mi = initial mass of neptunium = 4.00 grams
m = remaining mass of neptunium = ?
Therefore,
m = 4 grams/2⁴
<u>m = 0.25 gram</u>