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2 years ago

What causes the phases of the moon as observed from the Earth?

1 answer:

5 0

Your answer is D) The angle of light from the sun as it reflects off the moon and viewed from the Earth's surface because of the way the sun hits the moon one side has to light the other doesn't and when the moon rotates the sun hits another part of the moon.
If you need more help I would be glad to help!
*~"AB84"~*

You might be interested in

What does the red line in the diagram below represent?

bekas [8.4K]

Answer:

The activation energy

Explanation:

The activation energy is the energy hump that lies between reactants and products. It is the energy barrier that reactants must cross before they are converted into products.

Based on the collision theory, only particles that possess the activation energy are able to collide in such a way that leads to reaction.

Collision of particles having an energy content less than the activation energy of the reaction merely leads to elastic collision between such particles.

5 0

2 years ago

Calculate the solubility of copper(II) hydroxide, Cu(OH)2, in g/L

Oduvanchick [21]

Answer:

Ksp = [ Cu+² ] [ OH-] ²

molar mass Cu(oH )2 ==> M= 63.546 (1) + 16 (2) + 1 (2) = 97.546 g/mol

Ksp = [ Cu+² ] [ OH-] ²

Ksp [ cu (OH)2 ] = 2.2 × 10-²⁰

|__________|___Cu+² __|_2OH-____|

|Initial concentration(M)|___0__|_0______|

|Change in concentration(M)|_+S |__+2S__|

|Equilibrium concentration(M)|_S _|2S___|

Ksp = [ Cu+² ] [ OH-] ²

2.2 ×10-²⁰ = (S)(2S)²= 4S³

$s = \sqrt[3]{ \frac{2.2 \times {10}^{ - 20} }{4} } = 1.8 \times {10}^{ - 7}$

S = 1.8 × 10-⁷ M

The molar solubility of Cu(OH)2 is 1.8 × 10-⁷ M

Solubility of Cu (OH)2 =

$Cu (OH)2 = \frac{1.8 \times {10}^{ - 7} mol \:Cu (OH)2 }{1L} \times \frac{97.546 \: g \: Cu (OH)2}{1 \: mol \: Cu (OH)2} \\ = 1.75428 \times 10 ^{ - 5}$

<h3>Solubility of Cu (OH)2 = 1.75428 × 10 -⁵ g/ L</h3>

I hope I helped you^_^

8 0

2 years ago

What is the percent by mass of water in Na S04.10H20?

dalvyx [7]

Answer:

Percent by mass of water is 56%

Explanation:

First of all calculate the mass of hydrated compound as,

Mass of Sodium = Na × 2 = 22.99 × 1 = 45.98 g

Mass of Sulfur = S × 1 = 32.06 × 1 = 32.06 g

Mass of Oxygen = O × 14 = 16 × 14 = 224 g

Mass of Hydrogen = H × 20 = 1.01 × 20 = 20.2 g

Mass of Na₂S0₄.10H₂O = 322.24 g

Secondly, calculate mass of water present in hydrated compound. For this one should look for the coefficient present before H₂O in molecular formula of hydrated compound. In this case the coefficient is 10, so the mass of water is...

Mass of water = 10 × 18.02

Mass of water = 180.2 g

Now, we will apply following formula to find percent of water in hydrated compound,

%H₂O = Mass of H₂O / Mass of Hydrated Compound × 100

Putting values,

%H₂O = 180.2 g / 322.24 g × 100

%H₂O = 55.92 % ≈ 56%

3 0

2 years ago

2H2 + O2 --> 2H2O can be classified as what type of reaction?

Sveta_85 [38]

Combustion reaction
Key: O2
O2 is normally in a chemical formula when you are used to burn anything, so basically, anything with O2 involves burning.

5 0

2 years ago

Read 2 more answers

Chuẩn Độ 15 ml dung dịch CH3COOH 0,2 m bằng dung dịch NaOH 0,2 m

mina [271]

Answer:

<h3>I don't know what is the answer of your question sorry never mind..</h3>

Explanation:

<h3>And please marks me as brainliest... </h3>

3 0

2 years ago