Answer:
Measure 20mL of the stock
Explanation:
All we need to do is to find the volume of the stock solution needed. This is illustrated below:
C1 = 2M
V1 =?
C2 = 0.400 M
V2 = 100mL
C1V1 = C2V2
2 x V1 = 0.4 x 100
Divide both side by 2
V1 = ( 0.4 x 100) /2
V1 = 20mL
Therefore, to prepare the solution, we will measure 20mL of the stock solution and make it up to the 100mL mark.
(1) CaCO3 is your answer. The positive ion is
and the negative
radical ion is
. There exists covalent bonds between the carbon and oxygen atoms in the
.
Answer:
0.86 moles H₂O
Explanation:
To solve this problem, it is important to first determine the balanced chemical equation. The balanced equation is necessary as it will provide the mole-to-mole ratio needed to convert between moles O₂ and moles H₂O.
The unbalanced equation:
C₈H₁₈ (l) + O₂ (g) ---> CO₂ (g) + H₂O (g)
<u>Reactants:</u> 8 carbon, 18 hydrogen, 2 oxygen
<u>Products:</u> 1 carbon, 2 hydrogen, 3 oxygen
As you can see, the equation is not balanced because there are unequal amounts of each element on both sides. Balancing the equation is a matter of guessing-and-checking to see which combination of coefficients work.
The balanced equation:
2 C₈H₁₈ (l) + 25 O₂ (g) ---> 16 CO₂ (g) + 18 H₂O (g)
<u>Reactants:</u> 16 carbon, 36 hydrogen, 50 oxygen
<u>Products:</u> 16 carbon, 36 hydrogen, 50 oxygen
Now that the equation is balanced, we can use the coefficients of O₂ and H₂O to construct our mole-to-mole ratio and perform our conversion. The final answer should have 2 sig figs to match the given value (1.2 moles). The state of matter is most likely not necessary to include in your final answer.
1.2 moles O₂ 18 moles H₂O
--------------------- x ----------------------- = 0.86 moles H₂O
25 moles O₂
<span>The right answer here is that the best explanation for why the rusting of an iron nail in the presence of water and oxygen is an oxidation-reduction reaction is answer B) electrons are transferred. This is the only answer that actually explains the chemical reasoning behind the reaction.</span>
<u>Answer:</u> The balanced half reaction is written below.
<u>Explanation:</u>
Reduction reaction is defined as the chemical reaction in which an atom gains electrons. The oxidation number of the atom gets reduced during this reaction.
When oxygen gas is reduced to oxide ions, the number of electron transferred are 2
The chemical equation for the reduction of oxygen gas to oxide ions follows:
Hence, the balanced half reaction is written above.
