Answer:
False
Explanation:
Every chemical element undergoes a reaction in order to fulfill the completion of their outermost shell. This is the case of nitrogen (symbol "N"), which is an element found in group 5 of the periodic table with atomic number 7 (i.e. 1s2 2s2 2p3). It possesses three valence electrons in it's outermost shell.
Looking at the configuration of the Nitrogen atom, it requires three electrons to complete its electron shell. Hence, nitrogen will enter a reaction in order to have its need for THREE ELECTRONS met in order to have its electron shell full.
Note that, nitrogen enters a chemical reaction to look for three electrons not three neutrons.
<span>Texture can change without causing a change in the substance because even if you make some changes it's still the same. </span>
This is a simple algebraic problem, specifically for the mixture type of problem. Let x be the mass of 40% solution and y be the mass of 70% solution. The first equation would then be:
x + y = 20 --> eqn 1
The second equation would be the mass balance shown below:
(x)(0.40) + y(0.70) = 20(0.52) --> eqn 2
Rearranging eqn 1,
x = 20 - y
Substitute this to eqn 2:
(20 - y)(0.40) + y(0.70) = 20(0.52)
Solve for y,
y = 8 grams
Finally, solve for x.
x = 20 - 8 = 12 grams
<em>Therefore, Serena needs 12 grams of the 40% solution and 8 grams of the 70% solution.</em>
