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3 years ago

Question 18 of 25

Chemistry

1 answer:

horsena [70]3 years ago

5 0

Answer:

Explanation:

If the atom is neutral, the sum of the core and valence electrons is the same as the number of protons, which is the atomic number of the element. So if the sum of the core and valence electrons in a neutral atom equals 25 , that is the number of protons in the atomic nucleus, and the atomic number of the element.

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morpeh [17]

Answer:

B .805 mL

Explanation:

Here, temperature is constant!

so we can use P1V1=P2V2

P1,V1 is pressure and volume in original condition

and P2V2, pressure and volume in new condition!

now, volume is given 900mL(=V1)

standard pressure is 1 atm i.e, 760mmHg(=P1)

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now we have,

P1V1=P2V2

i.e, 760mmHg×900mL=850mmHg×V2

i.e, V2={(900×760)/850 } mL

=804.75 mL

≈805mL

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