The piece of unknown metal is in thermal equilibrium with water such that Q of metal is equal to Q of the water. We write this equality as follows:
-Qm = Qw
Mass of metal (Cm)(ΔT) = Mass of water (Cw) (ΔT)
where C is the specific heat capacities of the materials.
We calculate as follows:
-(Mass of metal (Cm)(ΔT)) = Mass of water (Cw) (ΔT)
-68.6 (Cm)(52.1 - 100) = 42 (4.184) (52.1 - 20)
Cm = 1.717 -----> OPTION C
Answer:
2.93g
Explanation:first, let us calculate the number of mole of NaCl present in the solution. This is illustrated below:
Molarity = 0.5M
Volume = 100cm^3 = 100/1000 = 0.1L
Mole =?
Molarity = mole /Volume
Mole = Molarity x Volume
Mole of NaCl = 0.5 x 0.1 = 0.05mole
Now we can obtain the mass of NaCl as follows:
Molar Mass of NaCl = 23 + 35.5 = 58.5g/mol
Mole of NaCl = 0.05mol
Mass of NaCl =?
Mass = number of mole x molar Mass
Mass of NaCl = 0.05 x 58.5
Mass of NaCl = 2.93g
Explanation:
Given problem:
Find the molar mass of:
SO₃ and C₁₀H₈
Solution:
The molar mass of a compound is the mass in grams of one mole of the substance.
To solve this, we are going to add the individual atomic masses of the elements in the compound;
Atomic mass;
S = 32g/mol; O = 16g/mol; C = 12g/mol and H = 1g/mol
For SO₃;
= 32 + 3(16)
= 32 + 48
= 80g/mol
For C₁₀H₈
= 10(12) + 8(1)
= 120 + 8
= 128g/mol
Answer:
number of moles=volume/molar volume or mass/molar mass
