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3. The heat of neutralization reaction between hydrochloric acid and ammonia solution is – 53.4 kJ/mol.
In an experiment, 25.00 mL of 1.80M ammonia was mixed with 15.00 mL of 2.75M hydrochloric acid. Both solutions were at an initial temperature of 18.2°C.
a) Write the equation for the neutralization reaction.
b) Calculate the number of moles of reaction that occurs.
c) Calculate the resulting change in temperature and hence the final temperature of the reaction mixture.
In an experiment, 25.00 mL of 1.80M ammonia was mixed with 15.00 mL of 2.75M hydrochloric acid. Both solutions were at an initial temperature of 18.2°C.
a) Write the equation for the neutralization reaction.
b) Calculate the number of moles of reaction that occurs.
c) Calculate the resulting change in temperature and hence the final temperature of the reaction mixture.
1. A block of titanium metal (c = 0.544 J/g.°C) at a temperature of 94.0°C is added to a Styrofoam cup containing 76.0 mL of water at 17.2°C.
If the final temperature of the titanium and water is 28.9°C, calculate the mass of the block of titanium. (Apply the same assumptions as in Q.1)
2. A Styrofoam calorimeter contains 66.25g of water at a temperature of 21.41˚C. 4.50g of potassium chlorate crystals are added to the water. When the crystals have dissolved completely, the water temperature has dropped to 16.28˚C.
Use this data to calculate the heat of solution of potassium chlorate in kJ/mole.
If the final temperature of the titanium and water is 28.9°C, calculate the mass of the block of titanium. (Apply the same assumptions as in Q.1)
2. A Styrofoam calorimeter contains 66.25g of water at a temperature of 21.41˚C. 4.50g of potassium chlorate crystals are added to the water. When the crystals have dissolved completely, the water temperature has dropped to 16.28˚C.
Use this data to calculate the heat of solution of potassium chlorate in kJ/mole.
a quantity of 14.68 mL of a KOH solution is needed to neutralize o.4018 g of KHP. what is the concentration (in molarity) of the KOH solution? (the molar mass of KHP is 204.2 g/moL.)
What mass of KCl would be recovered if 55 mL of 0.20 M KCl were “evaporated to dryness”?
[Hint: this is the same as asking how many grams of KCl are in 55 mL of 0.20 M KCl.]
[Hint: this is the same as asking how many grams of KCl are in 55 mL of 0.20 M KCl.]
Calculate the heat change associated with cooling a 400g iron bar from 126C to 40C. ( Cp= .44)
It is believed that humans first arrived in the Western Hemisphere during the
last Ice Age, presumably by traveling over an exposed land bridge between
Siberia and Alaska. Archaeologists have estimated that this occurred about
11,000 yr ago, but some argue that recent discoveries in several sites in North
and South America suggest a much earlier arrival. Analysis of a sample of
charcoal from a fire in one such site gave a 14C decay rate of 0.4 dpm/g of
carbon. What is the approximate age of the sample?
last Ice Age, presumably by traveling over an exposed land bridge between
Siberia and Alaska. Archaeologists have estimated that this occurred about
11,000 yr ago, but some argue that recent discoveries in several sites in North
and South America suggest a much earlier arrival. Analysis of a sample of
charcoal from a fire in one such site gave a 14C decay rate of 0.4 dpm/g of
carbon. What is the approximate age of the sample?
Cu(s)+Ni^ 2+ (aq) Ni(s)+Cu^ 2+ (aq)
During normal conditions the respiratory gases were mixed 25 dm3 of carbon dioxide with 10 dm3 of oxygen. Express the composition of gas mixture in the volume percentage.
A sample containing ammonium chloride was warmed with 100 mL of 1.00 moldm-3 sodium
hydroxide. After all the ammonia had been driven off, the excess sodium hydroxide required
50.00 mL of 0.250 moldm-3 sulfuric acid for neutralisation. What mass of ammonium chloride did
the sample contain?
hydroxide. After all the ammonia had been driven off, the excess sodium hydroxide required
50.00 mL of 0.250 moldm-3 sulfuric acid for neutralisation. What mass of ammonium chloride did
the sample contain?
The chlorine present in PVC has two stable isotopes. 35Cl with a mass of 34.97 amu and 37CI with a mass of 36.95 amu. Given chlorine's atomic mass of 35.45, what is the percent abundance of each isotope?
