Answer:
0.25M HCl
Explanation:
The reaction of HCl with NaOH is:
HCl + NaOH ⇄ H₂O + NaCl
<em>Where 1 mole of HCl reacts per mole of NaOH</em>
The end point was reached when the student added:
0.0500L × (0.1mol / L) = 0.00500 moles of NaOH
As 1 mole of HCl reacted per mole of NaOH, moles of HCl present are:
<em>0.00500 moles HCl</em>
The volume of the sample of hydrochloric acid was 20.0mL = 0.0200L, and concentration of the sample is:
0.00500 mol HCl / 0.0200L = <em>0.25M HCl</em>
C₄H₉OH + HBr = C₄H₉Br + H2O
Δmole of alcohol gives 1 mole of bromobutanol
HBr is in excess, so the yield of the product is limited by the alcohol
Wt. of 1 butanol = 18
Molar mass of the butanol = 74.12 g/mole
Moles of the alcohol = 1/74.12 = 0.01349 moles
So, moles of bromobutane = 0.01349 moles
Molar mass of C₄H₉Br = 137.018 g/moles
So, theoretical mass of bromobutane is = 0.01349 × 137.0.18
= 1.85 g
The density of ice is less than the density of water (liquid). We generally observe that the density of a solid substance is more than its liquid form as volume of a solid is generally less than the liquid, However in case of water this is not true.
The volume of ice is less than that of liquid water due to an open cage like structure in ice which gives its a wide structure. This cage like structure is due to presence of hydrogen bond (more extensive) in ice.
The maximum density of water is observed at 4 degree celsius
