to the proper number of significant figures) to the following? (12.67+19.2)(3.99)/(1.36+ 11.366).
When heat energy is supplied to a material it can raise the temperature of mass of the material.
Specific heat is the amount of energy required by 1 g of material to raise the temperature by 1 °C.
equation is
H = mcΔt
H - heat energy
m - mass of material
c - specific heat of the material
Δt - change in temperature
substituting the values in the equation
120 J = 10 g x c x 5 °C
c = 2.4 Jg⁻¹°C⁻¹
Combustion of any hrdrocarbon yields carbon dioxide and water such that the hydrogen and carbon are derived from the hydrocarbon.
1 mole of carbon dioxide has a mass out of which 12 g is the mass of carbon, therefore, 3.38 g of carbon will contain (3.38 × 12)/44 = 0.922 g of carbon.
Thus, since the hydrocarbon has a mass of 1 g, then the mass of hydrogen will be (1-0.922 g) = 0.078 g.
To get the empirical formula we divide the mass of each element by the atomic mass to get the number of moles.
Carbon= 0.922/12 = 0.0768 moles
Hydrogen = 0.078/1 = 0.078 moles
Then we get the ratio of the moles of carbon : hydrogen
= 0.0768 : 0.078
= 1 : 1.016
≈ 1: 1
Therefore the empirical formula of the hydrocarbon will be CH
Answer: the molarity of the solution in volumetric flask "B' is 0.0100 M
Explanation:
Given that;
the Molarity of stock solution M₁ = 1.25M
The molarity os solution in volumetric flask A (M₂) = M₂
Volume of stock solution pipet out (V₁) = 5.00mL
Volume of solution in volumetric flask A V₂ = 25.00mL
using the dilution formula
M₁V₁ = M₂V₂
M₂ = M₁V₁ / V₂
WE SUBSTITUTE
M₂ = ( 1.25 × 5.00 ) / 25.00 mL
M₂ = 0.25 M
Now volume of solution pipet out from volumetric flask A V₂ = 2.00 mL
Molarity of solution in volumetric flask B (M₃) = M₃
Volume of solution in volumetric flask B V₃ = 50.00m L
Using dilution formula again
M₂V₂ = M₃V₃
M₃ = M₂V₂ / V₃
WE SUBSTITUTE
M₃ = ( 0.25 × 2.0) / 50.0
M₃ = 0.0100 M
Therefore the molarity of the solution in volumetric flask "B' is 0.0100 M
Answer:
[CO] = 7.61x10⁻³M
7.61x10⁻³x10³ = 7.61
Explanation:
For a generic equation aA + bB ⇄ cC + dD, the constant of equilibrium (Kc) is:
![Kc = \frac{[C]^cx[D]^d}{[A]^ax[B]^b}](https://tex.z-dn.net/?f=Kc%20%3D%20%5Cfrac%7B%5BC%5D%5Ecx%5BD%5D%5Ed%7D%7B%5BA%5D%5Eax%5BB%5D%5Eb%7D)
We need to know the molar concentrations in the equilibrium. In the beginning, there is only COCl₂, and its concentration is the number of moles divided by the volume:
[COCl₂] = 7.73/10.0 = 0.773 M
So, the equilibrium will be:
COCl₂(g) ⇆ CO(g) + Cl₂(g)
0.773 0 0 <em>Initial</em>
-x +x +x <em> Reacts</em>
0.773-x x x <em>Equilibrium</em>
Supposing that x<<0.773, then:

7.5x10⁻⁵ = x²/0.773
x² = 5.7975x10⁻⁵
x = √5.7975x10⁻⁵
x = 7.61x10⁻³ M
The supposing is correct, so [CO] = 7.61x10⁻³ x 10³ = 7.61