How does an electron emit light?

Consider the following molecule.<br> 1. How many bonding pair of electrons are present?

Artemon [7]

Answer:

There are 3 bonding pairs of electrons

Explanation:

For every bond there is one bonded pair of electrons. NH₃ has three N-H bonds, so has three bonding pairs of electrons along with a lone pair of electrons

5 0

3 years ago

When the distance between two objects increases, the gravitational force between them _____.

Damm [24]

The force between them decreases

6 0

4 years ago

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2. Petroleum is used to make

Nonamiya [84]

Answer:

D. all of the above

Explanation:

5 0

3 years ago

If 42.7 of 0.208 M hydrochloric acid are needed to completely neutralize a solution of calcium hydroxide, how many grams of calc

Montano1993 [528]

Answer:

0.329 g

Explanation:

In the context of this problem, we have a chemical reaction between hydrochloric acid and calcium hydroxide. HCl is the acid here and calcium hydroxide is the base. Hence, we have an acid-base reaction, also known as neutralization reaction.

In a neutralization reaction, water is produced as a product, as well as a salt that we obtain after we exchange the cations: calcium bonds to chloride and hydrogen bonds to hydroxide (the latter is the formation of water). This means we also produce calcium chloride as a product. The overall reaction represents this as:

$Ca(OH)_2(aq)+2 HCl (aq)\rightarrow CaCl_2 (aq)+2 H_2O (l)$

Firslt of all, we wish to find the number of moles of HCl present. Having molarity and volume, this is done by applying the molarity formula. It states that molarity is equal to the rate between moles and volume:

$c_{HCl}=\frac{n_{HCl}}{V_{HCl}}$

Rearranging for moles of HCl, n:

$n_{HCl}=c_{HCl}V_{HCl}$

Based on stoichiometry of the balanced chemical equation, notice that 1 mole of calcium hydroxide reacts with 2 moles of HCl, meaning:

$n_{Ca(OH)_2}=\frac{1}{2} n_{HCl}=\frac{1}{2}c_{HCl}V_{HCl}$

Now that we have the expression for moles, we may also express moles of calcium hydroxide as the ratio between its mass and molar mass:

$n_{Ca(OH)_2}=\frac{m_{Ca(OH)_2}}{M_{Ca(OH)_2}}$

Using the last two equations, we see that:

$\frac{1}{2}c_{HCl}V_{HCl}=\frac{m_{Ca(OH)_2}}{M_{Ca(OH)_2}}\\\therefore m_{Ca(OH)_2}=\frac{1}{2}c_{HCl}V_{HCl}M_{Ca(OH)_2}$

Substitute the given data, as well as the molar mass of calcium hydroxide:

$m_{Ca(OH)_2}=\frac{1}{2}\cdot0.208 M\cdot0.0427 L\cdot74.093 g/mol=0.329 g$

8 0

4 years ago

When you see or visit grasslands, what do you know about the climate? (Select all that apply.)

Nana76 [90]

When you see or visit grasslands you know that :

They have mild to hot summers ( B )
They have a lot of precipitation ( A )

<h3><u>Grassland vegetation</u> </h3>

Grasslands are a type of vegetation found mostly in areas with favourable weather conditions such as mild summers and right amount of precipitation which provides the grasslands with enough water for proper growth.

Other types of vegetation include :

Forest vegetation
Tundra and
Desert vegetation

Desert vegetation expreciences very hot summers and little precipitation which leads to the scarcity of green vegetation, while forest vegetation expreciences a very high level of precipitation.

Hence we can conclude that When you see or visit grasslands you know that :They have mild to hot summers ,They have a lot of precipitation

Learn more about grasslands : brainly.com/question/994161

4 0

3 years ago

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