Answer:
The answer to your question is 178.6 g
Explanation:
Data
ΔT = 1.8 °C
mass = 17.5 g
mass of water = 100 g
Kc = 1.86
Process
1.- Calculate the molality using the following formula
ΔTc = mKc
solve for m
m = ΔTc/Kc
substitution
m = 1.8/1.86
result
m = 0.968
2.- Calculate the number of moles
m = # of moles/kg of solvent
kg of solvent = 0.1 kg
# of moles = m x kg of solvent
# of moles = 0.968 x 0.1
# of moles = 0.0968
3.- Calculate the molar mass
x g molar mass --------------------- 1 mol
17.5 g --------------------- 0.0968 moles
x = (1 x 17.5)/0.0968
x = 178.6 g
<span>Endothermic reactions take in heat from the environment in order to react while exothermic reactions release heat during the reaction. For this, D must be true as the products have less energy because they have released heat during the reaction. A and C are incorrect because they products and reactants are equal and B is wrong because the energy of the products would be more as the reaction took in heat.</span>
Electrons = protons
protons = atomic number
protons + neutrons = atomic mass
Therefore: a) protons + 7 = 15
protons= 15 -7
protons= 8
B) Remember proton = atomic number
so atomic number = 8
C)Now we know the atomic number so we can easily check on the periodic table what element has an atomic number of 8, which is Oxygen
A- Change the phase of the matter