Hi, here is a basic summary of what we did in a lab; there were 3 reactions: The procedure: Reaction 1: Solid sodium hydroxide dissolves in water to form an aqueous solution of ions. NaOH(s)-> Na+(aq) + OH-(aq) ΔH1=-34.121kJ Reaction 2: Solid sodium hydroxide reacts with an aqueous solution of HCl to form water and an aqueous solution of sodium chloride. NaOH(s) + H+(aq) + Cl-(aq) -> H2O + Na+(aq) + Cl-(aq) ΔH2=-83.602kJ Reaction 3: An aqueous solution of sodium hydroxide reacts with an aqueous solution of HCl to form water an an aqueous solution of sodium chloride. H+(aq) + OH-(aq) + Na+(aq) + Cl-(aq) -> H2O + Na+(aq) + Cl-(aq) ΔH3= -50.2kJ The ΔH values were calculated by dividing the heat gained by the number of moles (each reaction had 0.05moles of NaOH) The problem: Net ionic equations for reaction 2 & 3: 2: NaOH(s) + H+(aq) -> H2O + Na+(aq) 3: H+(aq) + OH-(aq) -> H2O i) In reaction 1, ΔH1 represents the heat evolved as solid NaOH dissolves. Look at the net ionic equations for reactions 2 and 3 and make similar statements as to what ΔH2 and ΔH3 represent. ii) Compare ΔH2 with (ΔH1 + ΔH3). Explain in sentences the similarity between these two values by using your answer to #5 above. Attempt at answering: i) Firstly, ΔH2 represents the heat evolved as the hydrogen ion displaces the sodium ion, creating a single displacement reaction. ΔH3 represents the heat evolved as the hydrogen and hydroxide ion form water via a neutralization reaction. ii) ΔH2 is equal to (or supposed to be, this is a source of error while calculating) (ΔH1 + ΔH3). The similarity between these two values is that .. (this is where I get confused!)
Source https://www.physicsforums.com/threads/calorimetry-help-chemistry.399653/
Answer:
experiment can show the movement of pollutants through the groundwater!
Explanation:
When acids react with bases they produce salt and water such as:
HCl + NaOH → NaCl + H₂O
According to strength of acid and base, we have 4 types of salts:
salt of strong acid and strong base like: NaCl
salt of weak acid and strong base like: CH₃COONa
salt of strong acid and weak base like: NH₄Cl
salt of weak acid and weak base like: CH₃COONH₄
Answer:
a. V = 1000 mL
b. Denisty = 0.022 g/mL
Explanation:
a.
First we need to convert the volume of the Osmium into mL. For that purpose we are given the conversion unit as:
1 mL = 0.1 cL
Hence, the given volume of Osmium will be:
V = Volume of Osmium = 100 cL = (100 cL)(1 mL/0.1 cL) = 1000 mL
<u>V = 1000 mL</u>
b.
The density of Osmium is given by the following formula:
Density = mass/Volume
Denisty = 22 g/1000 mL
<u>Denisty = 0.022 g/mL</u>
