Obtaining crude oil for refining is an example of

A sample of wood with a mass of 30 g has its

anzhelika [568]

Answer:

0.086J/g°C

Explanation:

The following data were obtained from the question:

Mass (M) = 30g

Initial temperature (T1) = 10°C

Final temperature (T2) = 45°C

Change in temperature (ΔT) = T2 – T1 = 45°C – 10°C = 35°C

Heat (Q) released = 90J

Specific heat capacity (C) of wood =..?

We can obtain the specific heat capacity of the wood as follow:

Q = MCΔT

90 = 30 x C x 35

Divide both side by 30 x 35

C = 90/(30 x 35)

C = 0.086J/g°C.

Therefore, the specific heat capacity of the wood is 0.086J/g°C.

5 0

3 years ago

lord [1]

Answer:

$\boxed{6.08 \times 10^{23}}$

Explanation:

Data:

I = 2.15 A

t = 8 min 24 s

T = 26.0 °C

V = 65.4 mL

p = 774.2 To

1. Write the equation for the half-reaction

2H₂O ⟶ O₂ + 4H⁺ + 4e⁻

2. Calculate the moles of oxygen

$p = \text{774.2 To} \times \dfrac{\text{1 atm}}{\text{760 To}} = \text{1.0187 atm}$

V = 0.0654 L

T = (26.0 + 273.15) K = 299.15 K

$\begin{array}{rcl}pV& = & nRT\\1.0189 \times 0.0654 & = & n \times 0.08206 \times 299.15\\0.06662 & = & 24.55n\\\\n & = & \dfrac{0.06662}{24.55}\\\\n & = & 2.714 \times 10^{-3}\\\end{array}$

3. Calculate the moles of electrons

$\text{n} = \text{2.714 $\times 10^{-3}$ mol oxygen} \times \dfrac{\text{4 mol electrons}}{\text{ 1 mol ozygen}} = \text{ 0.01086 mol electrons}$

4. Calculate the number of coulombs

t = 8 min 24 s =504 s

Q = It = 504 s × 2.10 C·s⁻¹= 1058 C

5. Calculate the number of electrons

$\text{No. of electrons} = \text{1058 C} \times \dfrac{\text{1 electron}}{1.602 \times 10^{-19}\text{ C}} = 6.607 \times 10^{21}\text{ electrons}$

6. Calculate Avogadro's number

$N_{\text{A}} = \dfrac{6.607 \times 10^{21}}{0.01086} = \mathbf{6.08 \times 10^{23}}\\\\\text{The experimental value of Avogadro's number is } \boxed{\mathbf{6.08 \times 10^{23}}}$

3 0

4 years ago

Draw a Lewis structure for SO2 in which all atoms have a formal charge of zero. Explicitly showing the zero charges is optional.

Radda [10]

Answer:

See explanation and image attached

Explanation:

"A formal charge (FC) is the charge assigned to an atom in a molecule, assuming that electrons in all chemical bonds are shared equally between atoms, regardless of relative electronegativity" (chemlibretext).

We can obtain the formal charge from the formula;

Formal Charge = [number of valence electrons on atom] – [non-bonded electrons + 1/2number of bonds].

A structure in which SO2 has a zero formal charge is attached to this answer.

Image credit: Chemtopper