Answer:
#1
Heat transfer occurred in the room through radiation
This is where heat is transmitted through vacuum or an empty space from a point to another.
#2
From the furnace, the air molecules nearer the region gained higher kinetic energy hence colliding with other molecules in the room. This causes a positive temperature gradient which causes an increment change in temperature in the room.

Answer : The percent by mass of water the salt contain is, 55.3 %
Explanation : Given,
Mass of hydrated salt = 12.10 g
Mass of salt = 5.41 g
First we have to calculate the mass of water.
Mass of water = Mass of hydrate salt - Mass of salt
Mass of water = 12.10 g - 5.41 g
Mass of water = 6.69 g
Now we have to calculate the percent by mass of water the salt contain.

Now put all the given values in this expression, we get:


Therefore, the percent by mass of water the salt contain is, 55.3 %
Answer:
41.63g
Explanation:
Given parameters:
Volume of CaCl₂ = 500mL = 0.5L
Concentration = 0.75mol/L
Unknown:
Mass of the solute needed = ?
Solution:
The mass of the solute can be derived using the expression below;
Mass = number of moles x molar mass
But,
Number of moles = Concentration x Volume
So;
Mass = Concentration x Volume x molar mas
Molar mass of CaCl₂ = 40 + 2(35.5) = 111g/mol
Mass = 0.75 x 0.5 x 111 = 41.63g
Answer:
Carbon exists in several isotopes. ... Carbon-12 has 6 neutrons, carbon-13 has 7 neutrons, and carbon-14 contains 8 neutrons. Carbon-12 and 13 are stable isotopes, which means that the nucleus does not undergo radioactive decay. Carbon-14 possesses an unstable nucleus which undergoes radioactive decay.
Explanation: Trust me :)