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Gwar [14]
3 years ago
9

How many block shells are the d block and the f block​

Chemistry
1 answer:
HACTEHA [7]3 years ago
4 0

Answer:

1s, 3p, 5d, 7f

Explanation:

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Which of the following steps correctly converts 3 moles of fluorine to an equivalent number of particles of fluorine? Divide Avo
Eva8 [605]

Answer:

Multiply 3 by Avogadro's number.

Explanation:

The mole can be defined as the amount of a substance that contains Avogadro’s number of particles, 6.02 x 10²³.

For elementary particles:

Number of particles=

number of moles x 6.02 x10²³

From the question,

Number of moles = 3moles

Number of particles = 3 x 6.02 x10²³

8 0
3 years ago
Based on the molar masses. how can you tell that an equation is balanced
harkovskaia [24]
You can tell if each side of the equation has the same molar mass.
3 0
2 years ago
Which two substances are covalent compounds? * C6H12O6(s) and KI(s) C6H12O6(s) and HCl(g) KI(s) and NaCl(s) NaCl(s) and HCl(g)
Ray Of Light [21]

Answer: Option (b) is the correct answer.

Explanation:

A covalent compound is defined as the compound in which sharing of electrons take place between the combining atoms. Generally, when two or more non-metals chemically combine together the it will lead to the formation of a covalent compound.

For example, C_{6}H_{12}O_{6} and HCl is also a covalent compound.

And, a compound in which transfer of electrons occur between the combining atoms is known as an ionic compound. Whenever, a metal chemically combines with a non-metal then it will always lead to the formation of an ionic compound.

For example, KI is an ionic compound.

Thus, we can conclude that C_{6}H_{12}O_{6} and HCl are the two substances which are covalent compounds.

7 0
3 years ago
you can work a total of no more than 20 hours per week at you two jobs. Baby-sitting pays $5 per hour,and your job as a cashier
Dovator [93]
Where x represents the number of hours working as a babysitter and y represents the number of hours working as a cashier...

5x + 6y <u><</u> 90
x + y <u>></u> 20
<u />
5 0
3 years ago
At 63.5 C the vapor pressure of H2O is 175 torr and that of ethanol is 400 torr. A solution is made by adding equal masses of H2
xxTIMURxx [149]

Answer:

Moel fraction of ethanol in the solution = 0.28

Vapor pressure of the solution = 238 torr

Mole fraction of ethanol in the vapor = 0.47

Explanation:

Let's use 100 g of each substance as a calculus basis. Knowing that the molar mass of water is 18 g/mol and the molar mass of ethanol is 46 g/mol, the number of moles (n = mass/molar mass) of each one is:

nw = 100/18 = 5.56 mol

ne= 100/46 = 2.17 mol

The total number of moles is 7.73 mol, so the mole fraction of ethanol is

2.17/7.73 = 0.28

The mole fraction of water must be 0.72, so if we assume that the solution is ideal, by the Raoult's law, the solution vapor pressure is the sum of the multiplication of the mole fraction by the vapor pressure of each substance, thus:

P = 0.28*400 + 0.72*175

P = 238 torr

The partial pressure of each substance can be found by the multiplication of the molar fraction by the vapor pressure, thus:

Pw = 0.72*175 = 126 torr

Pe = 0.28*400 = 112 torr

To know the number of moles that is vaporized above the solution, we may use the ideal gas law:

PV = nRT

P/n = RT/V

R is the gas constant, T is the temperature and V is the volume, so they are the same for both water and ethanol, thus

Pw/nw = Pe/ne

126/nw = 112/ne

ne = (112/126)*nw

ne = 0.89nw

So, the mole fraction of ethanol is:

ne/(ne + nw) = 0.89nw/(0.89nw + nw) = 0.89/1.89 = 0.47

4 0
3 years ago
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