<u>Answer:</u>
Exothermic Reaction are those reaction, in which energy is released while in endothermic reaction are those, in which energy is absorbed.
<u>Explanation:</u>
First Reaction:
As in this reaction, energy is released
½H2(g) + ½I2(g) → HI(g), ΔH = +6.2 kcal/mole
so it is <em>exothermic reaction</em>
Second reaction:
As in this reaction, energy is absorbed
21.0 kcal/mole + C(s) + 2S(s) → CS2(l)
so it is <em>endothermic reactions</em>.
Answer:
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Explanation:
Answer:
Number of moles = 2.8 mol
Explanation:
Given data:
Number of moles of water = ?
Volume of water = 50 mL
Density of water = 1.00 g/cm³
Solution:
1 cm³ = 1 mL
Density = mass/ volume
1.00 g/mL = mass/ 50 mL
Mass = 1.00 g/mL× 50 mL
Mass = 50 g
Number of moles of water:
Number of moles = mass/molar mass
Number of moles = 50 g / 18 g/mol
Number of moles = 2.8 mol
Explanation:
As it is known that molarity is the number of moles present in a liter of solution.
Mathematically, Molarity = 
As it is given that molarity is 0.10 M and volume is 10.0 ml. As 1 ml equals 0.001 L. Therefore, 10.0 ml will also be equal to 0.01 L.
Hence, putting these values into the above formula as follows.
Molarity = 
0.10 M = 
no. of moles = 0.001 mol
As molar mass of KCN is equal to 65.12 g/mol. Therefore, calculate the mass of KCN as follows.
No. of moles = 
0.001 mol = 
mass = 0.06152 g
Thus, we can conclude that 0.06152 grams of KCN are in 10.0 ml of a 0.10 M solution.