The formula you need is: heat= specific heat x mass x ΔT
specific heat= 0.46 j/g-C
mass= 100.0 grams
ΔT= 40.2 - 15.0= 25.2C
heat= (0.46) x (100.0) x (25.2)= 1159.2 joules or 1200 joules (rounded off)
3) +7
I got this stupid question wrong so that you people don't have to. I simply hate chemistry and I wish it didn't exist. Kind of like this website that makes me explain the answer.
Trust me, the answer is correct
Answer:
No photoelectric effect is observed for Mercury.
Explanation:
From E= hf
h= Plank's constant
f= frequency of incident light
Threshold Frequency of mercury= 435×10^3/ 6.6×10^-34 × 6.02×10^23
f= 11×10^14 Hz
The highest frequency of visible light is 7.5×10^14. This is clearly less than the threshold frequency of mercury hence no electron is emitted from the mercury surface
Answer:
Explanation:
14:
a) Shared pairs = 6
per shared pair between each C-H bond.
and two shared pair between C=C thus total shared pairs are 6
a) Lone pairs = 0
b) Single bonds = 4
Double bonds = 1
Triple bonds = 0
c) Formula = C₂H₄
Name = Ethene
d) Lewis structure = given structure is also Lewis structure.
13:
a) Shared pairs = 3
a) Lone pairs = 2
b) Single bonds = 0
Double bonds = 0
Triple bonds = 1
c) Formula = N₂
Name = Dinitrogen
d) Lewis structure = given structure is also Lewis structure.
The answer is 341.7 g.
(1) Calculate the molar mass (M) of CaCl2 which is the sum of atomic masses (A) of elements:
M(CaCl2) = A(Ca) + 2A(Cl)
A(Ca) = 40.1 g/mol
A(Cl) = 35.45 g/mol
M(CaCl2) = 40.1 + 2 * 35.45 = 40.1 + 70.9 = 111 g/mol
(2) Calculate in how many moles are 535 g:
M(CaCl2) = 111 g/mol
111g : 1mol = 535 g : xmol
x = 535 g * 1mol : 111g = 4.82 mol
(3) Calculate how many grams of Cl are in 4.82 mol:
A(Cl) = 35.45 g/mol
2A(Cl) = 2 * 35.45 = 70.9 g/mol
70.9 g : 1 mol = x : 4.82 mol
x = 70.9 g * 4.82 mol : 1 mol = 341.7 g
