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2 years ago

What is the significance of carbon having four valence electrons?

Chemistry

1 answer:

Dmitry_Shevchenko [17]2 years ago

6 0

Answer:

Sorry for the late answer, but it should be A. Carbon's outermost shell can form up to 4 covalent bonds. It's one of the reasons why Carbon is considered an "essential element".

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1) For the following molecules: - Draw the Lewis structures/dots - Determine the polarity (polar or non-polar). - List all inter

4vir4ik [10]

Answer:

Explanation:

8 0

2 years ago

What is the purpose of graphics in scientific articles

kow [346]

Answer:

Graphics can sometimes convey more information in a brief amount of space than an author can explain in a paragraph.

4 0

2 years ago

Dolomite is a mixed carbonate of calcium and magnesium. Calcium and magnesium carbonates both decompose upon heating to produce

Setler79 [48]

Answer:

72.03 %

Explanation:

Total mass of dolomite = 9.66 g

Let the mass of Magnesium carbonate = x g

The mass of calcium carbonate = 9.66 - x g

Calculation of the moles of Magnesium carbonate as:-

Molar mass of Magnesium carbonate = 122.44 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$Moles= \frac{x\ g}{84.3139\ g/mol}=\frac{x}{84.3139}\ mol$

Calculation of the moles of calcium carbonate as:-

Molar mass of calcium carbonate = 100.0869 g/mol

Thus,

$Moles= \frac{9.66 - x\ g}{100.0869\ g/mol}=\frac{9.66 - x}{100.0869}\ mol$

According to the reaction shown below:-

$MgCO_3\rightarrow MgO+CO_2$

$CaCO_3\rightarrow CaO+CO_2$

In both the cases, the oxides formed from the carbonates in the 1:1 ratio.

So, Moles of MgO = $\frac{x}{84.3139}\ mol$

Molar mass of MgO = 40.3044 g/mol

Thus, Mass = Moles*Molar mass = $\frac{x}{84.3139}\times 40.3044 \ g$

Moles of CaO = $\frac{9.66 - x}{100.0869}\ mol$

Molar mass of CaO = 56.0774 g/mol

Thus, Mass = Moles*Molar mass = $\frac{9.66 - x}{100.0869}\times 56.0774 \ g$

Given that total mass of the oxide = 4.84 g

Thus,

$\frac{x}{84.3139}\times 40.3044 +\frac{9.66 - x}{100.0869}\times 56.0774=4.84$

$\frac{40.3044x}{84.3139}+56.0774\times \frac{-x+9.66}{100.0869}=4.84$

$-694.1618435x+45673.48749\dots =40843.38968\dots$

$x=\frac{4830.09780\dots }{694.1618435}$

$x=6.9582$

Thus, the mass of Magnesium carbonate = 6.9582 g

$\%\ mass=\frac{Mass_{MgCO_3}}{Total\ mass}\times 100$

$\%\ mass=\frac{6.9582}{9.66}\times 100=72.03\ \%$

3 0

2 years ago

Calculate the vapor pressure of water at T=90°C

LenKa [72]

The equilibrium vapour pressure is typically the pressure exerted by a liquid .... it is A FUNCTION of temperature...

Explanation:

By way of example, chemists and physicists habitually use

saturated vapour pressure

...where

SVP

is the vapour pressure exerted by liquid water. At

100

∘

SVP

⋅

. Why?

Well, because this is the normal boiling point of water: i.e. the conditions of pressure (i.e. here

⋅

) and temperature, here

100

∘

, at which the VAPOUR PRESSURE of the liquid is ONE ATMOSPHERE...and bubbles of vapour form directly in the liquid. As an undergraduate you should commit this definition, or your text definition, to memory...

At lower temperatures, water exerts a much lower vapour pressure...but these should often be used in calculations...especially when a gas is collected by water displacement. Tables of

saturated vapour pressure

are available.

4 0

2 years ago

Round off the following number to 3 digits 34,560

Vikki [24]

Answer:

3.46x10⁴

Explanation:

Hello,

In this case, we can see that the number 34,560 has five significant figures, it means that if we want to write it with three, we must take the 3, 4 and 5 only. Nevertheless, since the 6 after the five is greater than 5, we can round such five to 6, so we obtain:

346

However, the decimal places cannot get lost, therefore, we move the given thousand to the three, so the number turns out:

3.46x10⁴

Best regards.

6 0

2 years ago