A) i believe the reaction is exothermic, because 27.6 kg of thermal energy is gained by the water solution, the dissolution of urea is exothermic. Exothermic reaction is a chemical reaction that releases energy by light or heat. It is the opposite of an endothermic reaction where heat is gained by the reaction.
b) The water gained the heat released when urea dissolve. That is the water gained 27.6 kJ, while dissolution of urea released 27.6 kJ. Therefore, the heat gained is equal to the heat lost.
c) From part B, since heat gained is equal to heal lost, then
250 g × (Tf -30) ×4.18 J/g = 27600 J
= 1045 Tf - 31350J = 27600 J
Tf = 56.41°C.
Therefore the final temperature of the solution is 56.41°C
d) The initial and final temperature in Fahrenheit
°F = °C × (9/5) +32,
Thus, 30°C will be equal to 86° F
while 56.41 will be equivalent to 133.54 ° F
Answer:
3 moles of CO are needed
Explanation:
Given data:
Number of moles of CO used = ?
Mass of Fe produced = 112 g
Solution:
Chemical equation:
Fe₂O₃ + 3CO → 2Fe + 3CO₂
Number of moles of Fe:
Number of moles = mass/ molar mass
Number of moles = 112 g/ 55.85 g/mol
Number of moles = 2.00 mol
Now we will compare the moles of iron and CO.
Fe : CO
2 : 3
Thus, 3 moles of CO are needed.
Answer:
Hi, a cheerful teen willing to help,
wishing you a splendiferous day ahead...
Explanation:
1ai. The most dense is Tungsten.
1aii. The least dense is Sodium.
1aiii. The strongest is Tungsten.
1b. All metals conduct electricity.
They are all magnetic except magnetic.
and all solid at room temperature except mercury.
1c. Mercury is a liquid at room temperature.
1d. Tungsten is used as filament for light bulbs due to its high melting point and it doesn't oxidize, this the filament won't melt.
1e. The lump of gold will sink because it is more dense than mercury.
<span>35.0 mL of 0.210 M
KOH
molarity = moles/volume
find moles of OH
do the same thing for: 50.0 mL of 0.210 M HClO(aq) but for H+
they will cancel out: H+ + OH- -> H2O
but you'll have some left over,
pH=-log[H+]
pOH
=-log[OH-]
pH+pOH
=14</span>