Answer:
The answer is (H30+) =3,55e-8M and (OH-)=2,82e-7M
Explanation:
We use the formulas:
pH= - log(H30+) and Kwater=(H30+)x(OH-)
pH= - log(H30+) ----< (H30+)= antilog- pH=antilog- 7,45=3,55E-8M
Kwater=(H30+)x(OH-)
(OH-)=Kwater/(H30+)= 1,00e-14/3,55e-8 = 2,82e-7
Answer:
see explanation below
Explanation:
You are missing the reaction scheme, but in picture 1, I found a question very similar to this, and after look into some other pages, I found the same scheme reaction, so I'm gonna work on this one, to show you how to solve it. Hopefully it will be the one you are asking.
According to the reaction scheme, in the first step we have NaNH2/NH3(l). This reactant is used to substract the most acidic hydrogen in the alkine there. In this case, it will substract the hydrogen from the carbon in the triple bond leaving something like this:
R: cyclopentane
R - C ≡ C (-)
Now, in the second step, this new product will experiment a SN2 reaction, and will attack to the CH3 - I forming another alkine as follow:
R - C ≡ C - CH3
Finally in the last step, Na in NH3 are reactants to promvove the hydrogenation of alkines. In this case, it will undergo hydrogenation in the triple bond and will form an alkene:
R - CH = CH - CH3
In picture 2, you have the reaction and mechanism.
The heat cause 300g water temperature increase from 20 to 26 celcius. The heat transferred would be: 300g * (26 °C -20 °C) *4.2 joule/gram °C= 7560J
The unknown substance is added to the water, so its final temperature should be the same as the water. The calculation would be:
7560J= 124g * (100-26)* specific heat
specific heat= 7560J / 124g / 74 °C= 0.8238 J/gram °C
Answer:
806.3g
Explanation:
Given parameters:
Number of moles of silver nitrate = 4.85mol
Unknown:
Mass of silver chromate = ?
Solution:
2AgNO₃ + Na₂CrO₄ → Ag₂CrO₄ + 2NaNO₃
To solve this problem, we work from the known to the unknown;
- The known specie here is AgNO₃ ;
From the balanced chemical equation;
2 moles of AgNO₃ will produce 1 mole of Ag₂CrO₄
4.85 moles of AgNO₃ will produce 
= 2.43moles of Ag₂CrO₄
- Mass of silver chromate produced;
mass = number of moles x molar mass
Molar mass of Ag₂CrO₄
Atomic mass of Ag = 107.9g/mol
Cr = 52g/mol
O = 16g/mol
Input the parameters and solve;
Molar mass = 2(107.9) + 52 + 4(16) = 331.8g/mol
So,
Mass of Ag₂CrO₄ = 2.43 x 331.8 = 806.3g
<h3>1. <u>Answer;</u></h3>
a. the strong nuclear force is much greater than the electric force.
<h3><u>Explanation</u>;</h3>
- <em><u>For an atom to be stable it means it has enough amount of binding energy to hold its nucleus together permanently. </u></em>
- Therefore, <em><u>an unstable atom lacks enough amount of binding energy to hold its nucleus permanently and thus undergoes decay to achieve stability. Unstable atoms are therefore referred to being radioactive.</u></em>
-
Small atoms are stable; <u>this is because they have equal number of protons and neutrons and thus the protons and neutrons fill up energy levels while maximizing the strong force binding the nucleus together. </u>
<h3>9.<u> Answer;</u></h3>
b. change into a different element altogether.
Uranium-238 undergoes alpha decay. Therefore, uranium-238 will <em><u>change into a different element altogether</u></em>.
<h3><u>
Explanation;</u></h3>
- Unstable atoms undergo radioactive decay in order to achieve stability of their nucleus.
- <em><u>Uranium-238 is an example of such atom, which may undergo decay to achieve stability.</u></em>
- <em><u>Alpha decay is one of the types of decays,</u></em> others being beta decay and gamma decay. <em><u>In alpha decay the radioactive isotope undergoes decay such that its mass number is decreased by four and its atomic number is decreased by two.</u></em>
-
Therefore, <em><u>Uranium-238 undergoes alpha decay to form a different element whose mass number is 234 and atomic number is 90, known as thorium-234. </u></em>
