<span>The boiling point of a substance is higher than its freezing point</span>
First convert mass to number of moles. Molar mass
of H2C2O2 • 2H2O = 94 / mol
1.89g / (94 g / mol) = .02 mol H2C2O2 • 2H2O
Then we divide by 0.1 L, or 100 mL, and we get a
concentration of 0.2 M.
Since there are two positive ions (2 H+), therefore
normality is:
<span>0.4 N</span>
Answer:
mass of platinum = 2526.12 g
Explanation:
Given data:
Mass of water = 125 g
Initial temperature of water= 100.0°C
Initial temperature of Pt = 20.0°C
Final temperature = 235°C
Specific heat of Pt = 0.13 j/g°C
Specific heat of water = 4.184 j/g°C
Mass of platinum = ?
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = T2 - T1
Q(w) = Q(Pt)
m.c. (T2 - T1) = m.c.
(T2 - T1)
125 g × 4.184 j/g°C × (235°C - 100.0°C) = m × 0.13 j/g°C × (235°C - 20°C)
125 g × 4.184 j/g°C × 135°C = m × 0.13 j/g°C × 215°C
70605 j = m×27.95 j/g
m = 70605 j /27.95 j/g
m = 2526.12 g
Answer:
B. Chemical changes produce new substances; physical changes do not.
Explanation:
Physical changes only alter appearances, while chemical changes are interactions that create new chemical formulas.
