Answer:
<u>7.44 grams CaCl2 will produce 10.0 grams KCl.</u>
Explanation:
The equation is balanced:
I've repeated it here, with the elements corrected for their initial capital letter.
CaCl2( aq) K2CO3( aq) → 2KCl( aq) CaCO3( aq)
This equation tells us that 1 mole of CaCl2 will produce 2 moles of KCl.
If we want 10.0g of KCl, we need to convert that mass into moles KCl by dividing by the molar mass of KCl, which is 74.55 grams/mole.
(10.0 grams KCl)/(74.55 grams/mole) = 0.1341 moles of KCl.
We know that we'll need half that amount of moles CaCl2, since the balanced equation says we'll get twice the moles KCl for every one mole CaCl2.
So we'll need (0.1341 moles KCl)*(1 mole CaCl2/2moles KCl) = 0.0671 moles CaCl2.
The molar mass of CaCl2 is 110.98 grams/mole.
(0.0671 moles CaCl2)*(110.98 grams/mole) = 7.44 grams CaCl2
<u>7.44 grams CaCl2 will produce 10.0 grams KCl.</u>
Answer:
The range of [H⁺] is from 2.51 x 10⁻⁶ M to 6.31 x 10⁻⁶ M,
Explanation:
To answer this problem we need to keep in mind the <u>definition of pH</u>:
So now we <u>calculate [H⁺] using a pH value of 5.2 and of 5.6</u>:
-5.2 = log [H⁺]
= [H⁺]
6.31 x 10⁻⁶ M = [H⁺]
-5.6 = log [H⁺]
= [H⁺]
2.51 x 10⁻⁶ M = [H⁺]
Answer:
Mass of hydrogen produced is 0.07g.
Explanation:
Given data:
Mass of magnesium = 7.73 g
Mass of water = 1.31 g
Reaction yield = 88.2%
Mass of hydrogen produced = ?
Solution:
Chemical equation:
Mg + 2H₂O → Mg(OH)₂ + H₂
Number of moles of water:
Number of moles = mass/ molar mass
Number of moles = 1.31 g / 18 g/mol
Number of moles = 0.07 mol
Number of moles of magnesium:
Number of moles = mass/ molar mass
Number of moles = 7.73 g / 18 g/mol
Number of moles = 0.43 mol
Now we will compare the moles of water and magnesium with hydrogen.
Mg : H₂
1 : 1
0.43 : 0.43
H₂O : H₂
2 : 1
0.07 : 1/2×0.07 = 0.035
Mass of hydrogen:
Mass = number of moles × molar mass
Mass = 0.035 mol × 2 g/mol
Mass = 0.07 g
Answer: False
Explanation: The kinetic energy of the molecules is the energy possessed by virtue of motion of particles.
Kinetic energy of the particles is directly proportional to the temperature of the gas.
where T= temperature
R= gas constant
Thus if the particles are moving faster that means the kinetic energy is high, the temperature must be higher and the particles must feel hot to touch.
