Hydrogen reacts with oxygen based on the following equation:
2 H2<span> + O</span>2<span> → 2 H</span>2<span>O
</span>
From the periodic table:
molar mass of hydrogen = 1 gram
molar mass of oxygen = 16 grams
From the balanced equation above, we can find that:
4 grams of hydrogen react with 32 grams of oxygen to produce 36 grams of water.
This means that: 0.73 grams of hydrogen require (0.73x32) / 4 = 5.84 grams of oxygen to react with.
Since only 3.28 grams of oxygen are reacting, this means that oxygen is our limiting reagent and that the reaction would stop once the amount of oxygen is consumed.
So, we will base our calculations on oxygen.
mass of water produced from 3.28 grams of oxygen can be calculated as follows:
mass of water = (3.28 x 36) / 32 = 3.69 grams
Answer:
14. B 15. D 16. C 17. B
Explanation:
The spontaneous reaction that occurs when the cell operates is shown below:
⇒
We need to select the correct option from the list below for the following questions.
(A) Voltage increases. (B) Voltage decreases but remains > zero. (C) Voltage becomes zero and remains at zero. (D) No change in voltage occurs. (E) Direction of voltage change cannot be predicted without additional information.
14. A 50-milliliter sample of a 2-molar
solution is added to the left beaker.
If a 50-milliliter sample of a 2-molar
solution is added to the left beaker, the voltage decreases but its value remains greater than zero. The correct option is B
15. The silver electrode is made larger.
If the silver electrode is made larger, no change in the value of the voltage since we don't have the idea of the initial value. The correct option is D.
16. The salt bridge is replaced by a platinum wire.
If the salt bridge is replaced by a platinum wire, there will be no passage of electrons because electrons can't pass through a platinum wire. Therefore, the voltage will be zero and remains at zero. The correct option is C.
17. Current is allowed to flow for 5 minutes.
If current is allowed to flow for 5 minutes, the voltage decreases but its value remains greater than zero. The correct option is B.
Sodium chloride (NaCl), whose only changes about 5g/100mL water over that entire range 100°C)