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Phoenix [80]
2 years ago
11

21. an atom has 216 protons, how many electrons does it have?

Chemistry
1 answer:
yanalaym [24]2 years ago
4 0

Answer:

21: 47 22: 14

Explanation:

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what is the ratio of the rate of effusion of helium (atomic mass 4.00 amu) to that of oxygen gas (molecular mass 32.0 amu)?
nignag [31]

Answer:

3 : 1

Explanation:

Let the rate of He be R1

Molar Mass of He (M1) = 4g/mol

Let the rate of O2 be R2

Molar Mass of O2 (M2) = 32g/mol

Recall:

R1/R2 = √(M2/M1)

R1/R2 = √(32/4)

R1/R2 = √8

R1/R2 = 3

The ratio of rate of effusion of Helium to oxygen is 3 : 1

8 0
2 years ago
Which material is a mixture 1 water 2 air 3 methane 4 magnesium
amm1812

Answer: Air

Explanation: Pure air is a mixture of several gases that are invisible and odorless. Consists of 78% nitrogen, 21% oxygen, and less than 1% of argon, carbon dioxide.

8 0
3 years ago
What does the poitof incidence mean?​
Lemur [1.5K]

Answer:

Point of incidence: The point on the surface where the incident ray strikes the surface is called the point of incidence. Reflected ray: The ray of light that bounces back from the surface of an object is called a reflected ray of light.

Explanation:

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4 0
3 years ago
Select all of the following properties that are characteristics of true solutions
nataly862011 [7]

Answer:

number 4

Explanation:

3 0
2 years ago
The normal boiling point of a liquid is 282 °C. At what temperature (in °C) would the vapor pressure be 0.500 atm? (∆Hvap = 28.5
NNADVOKAT [17]

For a normal boiling point of a liquid is 282 °C, the temperature is mathematically given as

T2=181.55°C\

<h3> What temperature (in °C) would the vapor pressure be 0.500 atm? </h3>

Generally, the equation for the gas  is mathematically given as

ln(p1/p2)=dHvap/R(1/T2-1/T1)

Therefore

ln(1/0.26)=23500/8.214(1/T2-1/555)

T2=181.55^C

In conclusion

T2=181.55°C

Read more about Temperature

brainly.com/question/13439286

7 0
2 years ago
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