Answer:
70 mL of 5% HCl and 30 mL of 15% HCl
Explanation:
We will designate x to be the fraction of the final solution that is composed of 5% HCl, and y to be the fraction of the final solution that is composed of 15% HCl. Since the percentage of the final solution is 8%, we can write the following expression:
5x + 15y = 8
Since x and y are fractions of a total, they must equal one:
x + y = 1
This is a system of two equations with two unknowns. We will proceed to solve for x. First, an expression for y is found:
y = 1 - x
This expression is substituted into the first equation and we solve for x.
5x + 15(1 - x) = 8
5x+ 15 - 15x = 8
-10x = -7
x = 7/10 = 0.7
We then calculate the value of y:
y = 1 - x = 1 - 0.7 = 0.3
Thus 0.7 of the 100 mL will be the 5% HCl solution, so the volume of 5% HCl we need is:
(100 mL)(0.7) = 70 mL
Similarly, the volume of 15% HCl we need is:
(100 mL)(0.3) = 30 mL
Answer:
Xenon is less reactive.
Explanation:
Xenon is a noble gas with 8 valence electrons whereas bromine is a halogen with 7 and is very reactive.
Answer:
Oxygen.
Explanation:
Oxygen is a chemical element that aides in the burning of materials and it is needed for humans to breathe.
Cellular respiration can be defined as a series of metabolic reactions that typically occur in cells so as to produce energy in the form of adenosine triphosphate (ATP). During cellular respiration, high energy intermediates are created that can then be oxidized to make adenosine triphosphate (ATP). Therefore, the intermediary products are produced at the glycolysis and citric acid cycle stage through the breathing of oxygen used to obtain energy from the food ingested.
Hence, all cells in living organisms require oxygen and glucose to release energy.
Answer:
0.322 moles
Explanation:
Given Mass, m = 100 g
The molar mass of Ca₃(PO₄)₂
Ca₃(PO₄)₂ = (3 x 40.08) + (2 x 30.97) + (8 x 16.00)
M = 310.18 g/mol
Let there are n number of moles,
n = given mass/ molar mass
So, there are 0.322 moles.
= 18.02 g/mol) im sure its that
