To solve this we use the equation,
M1V1 = M2V2
where M1 is the concentration of the stock solution, V1 is the
volume of the stock solution, M2 is the concentration of the new solution and
V2 is its volume.
M1V1 = M2V2
40% x 30 L = 30% x V2
V2 = 40 L
Therefore, you will need to have 30 mL of the 40% acid solution
and 10 mL of distilled water. In mixing the two liquids, you should remember
that the order of mixing would be acid to water. So, you use a 40 mL volumetric flask . Put small amount of distilled water and add the 30 mL of HCl solution. Lastly, dilute with distilled water up to the mark.
Answer:
This question is incomplete
Explanation:
This question is incomplete. However, to determine the number of different element participating in a reaction, count the number of individual atoms participating the reaction. For example,
H₂SO₄ + 2NaOH ⇒ Na₂SO₄ + 2H₂O
The number of different elements involved in the reaction above are hydrogen (H), sulphur (S), oxygen (O) and sodium (Na). This means there are 4 different elements involved in the reaction.
But to determine the total number of atoms involved in a reaction, one must first ensured the reaction is balanced (because the number of each atom must be considered). Using the same reaction illustrated earlier hydrogen (H) has 2 atoms in H₂SO₄ and 2 atoms in NaOH, sulphur (S) has 1 atom in H₂SO₄, oxygen (O) has 4 atoms in H₂SO₄ and 2 atoms in NaOH and sodium (Na) has 2 atoms in NaOH. Thus, total number of atoms is 13 atoms.
Note that the number of atoms on the reactant side would be same as number of atoms on product side because of law of conservation of matter. Thus, participating atoms in the reaction is 13
Answer:
C₆H₁₈
Explanation:
Let's say x is the subscript of carbon and y is the subscript of hydrogen. We know from the empirical formula that the ratio of x to y is 2 to 6.
x / y = 2 / 6
We also know from the molar mass that:
12.01x + 1.01y = 90.21
Solving the system of equations:
2y = 6x
y = 3x
12.01x + 1.01(3x) = 90.21
12.01x + 3.03x = 90.21
15.04x = 90.21
x = 6
y = 3x
y = 18
The molecular formula is therefore C₆H₁₈.
Answer:
Isopropyl propionate
Explanation:
1. Information from formula
The formula is C₆H₁₂O₂. A six-carbon alkane would have the formula C₆H₁₄. The deficiency of two H atoms indicates the presence of either a ring or a double bond.
2. Information from the spectrum
(a) Triplet-quartet
A 3H triplet and a 2H quartet is the classic pattern for a CH₃CH₂- (ethyl) group
(b) Septet-doublet
A 1H septet and a 6H doublet is the classic pattern for a -CH(CH₃)₂ (isopropyl) group
(c) The rest of the molecule
The ethyl and isopropyl groups together add up to C₇H₁₂.
The rest of the molecule must have the formula CO₂ and one unit of unsaturation. That must be a C=O group.
The compound is either
CH₃CH₂-COO-CH(CH₃)₂ or (CH₃)₂CH-COO-CH₂CH₃.
(d) Well, which is it?
The O atom of the ester function should have the greatest effect on the H atom on the adjacent carbon atom.
The CH of an isopropyl is normally at 1.7. The adjacent O atom should pull it down perhaps 3.2 units to 4.9.
The CH₂ of an ethyl group is normally at 1.2. The adjacent O atom should pull it down to about 4.4.
We see a signal at 5.0 but none near 4.4. The compound is isopropyl propionate.
3. Summary
My peak assignments are shown in the diagram below.
Answer & explanation:
Summary on electrochemical cells and redox reactions:
Electrochemical cells (or batteries) can be defined as devices capable of transforming chemical energy into electrical energy through spontaneous reactions of redox, in which electron transfer occurs.
Redox it is a chemical reaction in which there is the occurrence of oxidation and reduction of atoms of substances (chemical species) present in the process.
<u>Oxidation</u> is the loss of electrons by an atom of a chemical species, while <u>reduction</u> is the gain of electrons by an atom of a chemical species.
Thus, during an oxirreduction reaction, electrons move from the species that loses them towards the species that will receive them. This "movement" results in the formation of an electric current (or electrical energy) as occurs with batteries, for example.
