Answer:
E) HBr
Explanation:
Because Bromine (Br) isn't part of the original formula for Apirin. (I answered this based on the assumption that the letter "A" in option C was a typo of sorts, since there is no element with a chemical symbol of just "A" that I am aware of. If this is incorrect, then I apologize.)
Answer:
Explanation:
1. Mass of zinc
The density of zinc is 7.14 g/cm³
D = m/V
2. Volume of aluminium
The density of aluminium is 2.60/cm³.
Answer:
pH = 4.78
Explanation:
<em>There are titrated 65.8mL of a 0.7600M of acetic acid</em>
The reaction of acetic acid, CH₃COOH, with NaOH is:
CH₃COOH + NaOH → CH₃COONa + H₂O
Initial moles of acetic acid are:
0.0658L ₓ (0.7600mol / L) = 0.05000 moles of CH₃COOH
Moles of NaOH added to the acid solution are:
0.0784L ₓ (0.3500mol / L) = 0.02744 moles of NaOH = Moles of CH₃COONa produced -<em>Because NaOH is the limiting reactant-</em>
That means after the reaction moles of CH₃COOH and moles of CH₃COONa are:
CH₃COOH: 0.05000 mol - 0.02744 mol = 0.02256 moles
CH₃COONa: 0.02744 moles
Using H-H equation for acetic acid, pH of the solution is:
pH = 4.70 + log₁₀ [CH₃COONa] / [CH₃COOH]
Replacing:
pH = 4.70 + log₁₀ [0.02744] / [0.02256]
<h3>pH = 4.78</h3>
Answer:
C
Explanation:
Single replacement reactions is when only one element gets replaced / changed. This usually looks like this: A + BC = B + AC or A + BC = C + AB
Therefore, the number of reactants must be equal to the number of products, since no actual combinations / break ups are occurring.
Answers A and D are eliminated right away since the number of products don't equal the number of reactants.
Answer B is wrong because it does not show simply one element being replaced, instead, two compounds are being formed. It doesn't look like the example given.
Only answer C shows that one element is replaced:
The iodine is replaced with bromine to form NaBr + I2
Answer:
No
Explanation:A single property is insufficient for identifying a substance