All categories

3 years ago

4. The picture shows a full moon.

Chemistry

2 answers:

Anuta_ua [19.1K]2 years ago

6 0

Answer:

A full moon occurs when the Moon appears as a complete circle in the sky.

Explanation:

- We see it as a full orb because the whole of the side of the Moon facing the Earth is lit up by the Sun's rays.

- The moon shows no visible light of its own, so we only see the parts of the moon that are lit up by other objects.

sineoko [7]2 years ago

3 0

The answer is d i hope this helps

You might be interested in

If you quickly plunge a room-temperature mercury thermometer into very hot water, what will happen to the mercury level?\

jeka57 [31]

The answer is; The mercury level first falls then begin to rise rapidly.

This is because even though glass is not a good thermal conductor, the great heat variation causes the glass to gather heat and expand first even before the mercury is reached by the heat. This increases the volume of the lumen of the glass hence causing the mercury level to drop as the volume of the glass increases.

however, as the heat reaches the mercury, it also begins to expand and the levels stop falling and begin to rise.

3 0

2 years ago

Make a quantitative and qualitative statement about the following:. water, carbon, iron, hydrogen gas, sucrose, table salt, merc

gladu [14]

The elements in this list are mercury, gold, iron, carbon and hydrogen. The compounds in this list, on the other hand, are sucrose, table salt, water and air. Elements are composed only of one substance while compounds are composed of two or more substances.

8 0

3 years ago

Read 2 more answers

Which of the following can be mixed in solution with H2CO3 to make a buffer?

Temka [501]

Answer:

Sodium hydroxide solution.

Explanation:

because it is a strong base. Since carbonic acid is a weak acid, a solution formed resists change in pH on addition hence buffer formed.

8 0

3 years ago

Which of the following is most likely to be a conductor

aleksandr82 [10.1K]

Answer:

A compound containing metallic bonds.

Explanation:

8 0

3 years ago

A civil engineering student is considering buying an electric car. However, the conscious student wants to make sure her carbon

svetlana [45]

Answer:

$\text{An gasoline-powered vehicle has }\\\boxed{\text{five times the carbon footprint}}\text{ of an electric vehicle.}$

Explanation:

1. Miles travelled in an average month

$\text{Miles} = \text{1 mo} \times \dfrac{\text{52 wk}}{\text{12 mo}} \times \dfrac{\text{5 da}}{\text{1 wk}} \times \dfrac{\text{16 mi}}{\text{1 da}} = \text{347 mi}$

2. Using a gasoline powered vehicle

(a) Moles of heptane used

$n = \text{347 mi} \times \dfrac{\text{1 gal}}{\text{36.5 mi}}\times \dfrac{\text{3.785 L}}{\text{1 gal}} \times \dfrac{\text{679.5 g}}{\text{1L}} \times \dfrac{ \text{1 mol}}{\text{100.20 g}}= \text{244 mol}$

(b) Equation for combustion

C₇H₁₆ + O₂ ⟶ 7CO₂ + 8H₂O

(c) Moles of CO₂ formed

$n = \text{244 mol heptane} \times \dfrac{\text{7 mol CO$_{2}$}}{\text{1 mol heptane}} = \text{1710 mol CO$_{2}$}$

(d) Volume of CO₂ formed

At 20 °C and 1 atm, the molar volume of a gas is 24.0 L.

$V = \text{1710 mol } \times \dfrac{\text{24.0 L}}{\text{1 mol}} \times \dfrac{\text{1 gal}}{\text{3.785 L}} = \textbf{10 800 gal}$

3. Using an electric vehicle

(a) Theoretical energy used

$\text{Theor. Energy} = \text{347 mi} \times \dfrac{\text{1 kWh}}{\text{5.2 mi}} = \text{66.7 kWh theor.}$

(b) Actual energy used

The power station is only 85 % efficient.

$\text{Actual energy used} = \text{66.7 kWh theor.} \times \dfrac{\text{100 kWh actual}}{\text{ 85 kWh theor.}}\times \dfrac{\text{3600 kJ}}{\text{1 kWh}}\\\\ = 2.82\times 10^{5} \text{ kJ}\$

(c) Combustion of CH₄

CH₄ + 2O₂ ⟶ CO₂ +2 H₂O

(d) Equivalent volume of CO₂

The heat of combustion of methane is -802.3 kJ·mol⁻¹

$V= 2.82\times 10^{5}\text{ kJ} \times \dfrac{\text{1 mol methane}}{\text{802.3 kJ}} \times \dfrac{\text{1 mol CO$_{2}$} }{\text{1 mol methane}} \times \dfrac{ \text{24.0 L}}{ \text{1 mol CO$_{2}$}}\\\\ \times \dfrac{\text{1 gal}}{\text{3.875 L}} = \textbf{2180 gal}$

4. Comparison

$\dfrac{V_{\text{gasoline}}}{V_{\text{electric}}} = \dfrac{10800}{2180} = 5.0\\\\ \text{An gasoline-powered vehicle has }\\ \boxed{\textbf{ five times the carbon footprint}}\text{ of an electric vehicle.}$

6 0

3 years ago