The atomic number is the number of protons in the nucleus of an atom. The number of protons define the identity of an element.
Answer:
The answer to your question is : letter B. 0.25 atm
Explanation:
To solve this problem we need to use the combined gas law:
<u>P₁V₁</u> = <u>P₂V₂</u>
T₁ T₂
Data
P1 = 0.99 atm V1 = 2 l T1 = 273K
P2 = ? V2 = 4 l T2 = 137K
Now, the clear P2 from the equation and we get
P2 = P1V1T2 / T1V2
Substitution P2 = (2 x 0.99 x 137)/(273 x 4)
P2 = 271.26 / 1092
Result P2 = 0.248 atm ≈ 0.25 atm
4. Snow removal, as its snows a lot in Pennsylvania.
5. For number 5 please tell me which services the company offers & keep in mind the weather patterns are pretty hot & sunny in Florida, especially during the summers. If the company provides services (such as snow removal) Florida would hardly need any, causing the company to make less profit.
Good luck & please be sure to try your best. You got this!
Answer:
0.375 grams are needed to make 25 mL solution.
Explanation:
Mass of
cuprous nitrate required to make 1 l of solution = 15 g.
1 L = 1000 mL
Mass of
cuprous nitrate required to make 1000 mL of solution = 15 g
Mass of
cuprous nitrate required to make 1 mL of solution:

Mass of
cuprous nitrate required to make 25 mL of solution:

0.375 grams are needed to make 25 mL solution.
Answer:The 1st and 2nd reactions are the example of oxidation -reduction.
Explanation:
Oxidation is basically when a species loses electrons and reduction is basically when the species gains electrons.
A reaction is known as an oxidation -reduction reaction only if oxidation and reduction simultaneously occur in the reaction. It basically means if a species is getting oxidized in the reaction then the other species present in the system must be reduced in the reaction.
Oxidation-reduction reactions are also known as redox reactions.
In the 1st reaction the oxidation state of Na in reactant is 0 and in products is +1 hence Na is oxidized and the oxidation state of chlorine is 0 in reactants and in products is -1 so chlorine is reduced. Hence Na is oxidized and Cl is reduced so the reaction is a example of oxidation-reduction.
2Na(s)+Cl₂(g)→2NaCl(s)
In the second reaction the oxidation state of Na in reactant is 0 and in products is +1 hence Na is oxidized and the oxidation state of Cu is +1 in reactant and 0 in products so Cu is reduced. Hence Na is oxidized and Cu is reduced so the reaction is an example of oxidation-reduction.
Na(s)+CuCl(aq)→NaCl(aq)+Cu(s)
In the third reaction the oxidation state of Na changes from +1 to +1 and that of Cu also changes from +1 to +1. So there is no change in oxidation state of the species present in reactants and products. Hence this reaction is not an example of oxidation and reduction.