Answer:
A.) 1
Explanation:
Propane only exists in one conformation. It does not have enough carbons to form branches, and there are only hydrogens attached to each carbon. Furthermore, there is no way to twist the carbon or change its orientation (ex. cis- and trans-) to result in a different structure of propane. There is no other way to represent the molecule without drawing a different molecule.
Explanation:
A physical change is one that alters the physical properties of matter (particularly the form and state).
A chemical change is one in which new kind of matter is formed. It is always accompanied by energy changes (evolution or absorption of energy in form of heat or light or both).
Now, the salient differences between physical and chemical changes;
- Physical changes are easily reversible whereas chemical changes are not easily reversible.
- Physical changes lead to the production of no new kinds of matter whereas chemical changes leads to the production of new kinds of matter.
- Physical changes involves no change in mass whereas chemical changes involves change in mass.
- Physical changes require little energy whereas considerable amount of energy is needed for chemical changes.
Answer:
The answer is 0.0698 M
Explanation:
The concentration was prepared by a serial dilution method.
The formula for the preparation I M1V1 = M2V2
M1= the concentration of the stock solution = 0.171 M
V1= volume of the stock solution taken = 200 mL
M2 = the concentration produced
V2 = the volume of the solution produced = 940 mL
Substitute these values in the formula
0.171 × 200 = 490 × M2
34.2 = 490 × M2
Make M2 the subject of the formula
M2 = 34.2/490
M2 = 0.069795
M2 = 0.0698 M ( 3 s.f)
The concentration of the Chemist's working solution to 3 significant figures is 0.0698M
The limiting reagent is <u>H₂SO₄</u>
<u><em>calculation</em></u>
<u><em> </em></u>Step 1 :write the equation for reaction
2 NaOH + H₂SO₄ → Na₂SO₄ + 2 H₂O
Step 2: use the mole ratio to determine the moles of product produced from each reactant
that is from equation above,
NaOH : Na₂SO₄ is 2 :1 therefore the moles of Na₂So₄
= 10.0 moles x 1/2 = 5.0 moles
H₂SO₄ :Na₂SO₄ is 1:1 therefore the moles of Na₂SO₄ is also = 3.50 moles
H₂SO₄ is the limiting reagent since it produces less amount of Na₂SO₄
