A. The number of valence electrons increases as atomic mass increases. == Generally true for the representative elements since atomic mass generally increases with increasing Z.
B. The reactivity of alkali metals increases as atomic mass increases. == True. Atomic mass increases down the column and so does reactivity
C. The reactivity of the halogens increases as atomic mass increases. == False. Reactivity decreases down the column.
D. The number of valence electrons decreases across a period. == False. In general, the number of valence electrons increases across a period, particularly for the representative elements.
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Answer:</h3>
43.33 atm
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Explanation:</h3>
We are given;
Mass of C₆H₆ = 26.2 g
Volume of the container = 0.25 L
Temperature = 395 K
We are required to calculate the pressure inside the container;
First, we calculate the number of moles of C₆H₆
Molar mass of C₆H₆ = 78.1118 g/mol.
But; Moles = mass ÷ Molar mass
Moles of C₆H₆ = 26.2 g ÷ 78.1118 g/mol.
= 0.335 moles C₆H₆
Second, we calculate the pressure, using the ideal gas equation;
Using the ideal gas equation, PV = nRT , Where R is the ideal gas constant, 0.082057 L.atm/mol.K
Therefore;
P = nRT ÷ V
= (0.335 mol × 0.082057 × 395 K) ÷ 0.25 L
= 43.433 atm
Therefore, the pressure inside the container is 43.33 atm
Answer:
<u>Who: </u>Svante Arrhenius.
When: Claimed in 1896 that fossil fuels has a negative effect on our atmosphere.
<u>How:</u> Svante Arrhenius proved that fossil fuels had a negative effect by calculating the output of buildings that emit fossil fuels, and lead to the conclusion by his calculations that the industry might one day bring global warming. Svante Arrhenius' theory of electrolytic dissociation and his model of the greenhouse effect also helped him to prove that his remarks about fossil fuels and global warming is true.
<u>Where:</u>
I cannot find any source that mentions the where. What do you mean by where?
I hope my other information help you. I apologies to only be able to answer partially.
Answer:
Because the optimal range of buffering for a formic acid potassium formate buffer is 2.74 ≤ pH ≤ 4.74.
Explanation:
Every buffer solution has an optimal effective range due to pH = pKa ± 1. Outside this range, there is not enough acid molecules or conjugate base molecules to sustain the pH without variation. There is a certain amount of both molecules that has to be in the solution to maintain a pH controlled.
Being for the formic acid the pKa 3.74, the optimal effective range is between 2.74 and 4.74. Upper or lower these range a formic acid/potassium formate buffer does not work.
