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3 years ago

What is the mass number of the isotope lithium-7??

Physics

2 answers:

svp [43]3 years ago

8 0

Explanation:

Mass number is the sum of total number of protons and total number of neutrons present in an atom.

For example, a neutral atom of lithium has mass number 7 and atomic number 3.

Atomic number means the total number of protons present in an atom.

So, isotope of lithium-7 will have 3 protons and 4 neutrons. Thus, mass number of lithium-7 will be 3 + 4 = 7.

FromTheMoon [43]3 years ago

5 0

Lithium-7 is by far the most-common isotope, making up about 92.5 percent of all natural lithium. A lithium-7 atom contains three protons, four neutrons, and three electrons.

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ikadub [295]

Answer:

the last one, It moves away from a mid-ocean ridge.

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2 years ago

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Fofino [41]

Answer:

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Water will not enter the chamber if the pressure of air in it equals that of the water which tries to enter it.

Thus at a depth of 60m we have pressure of water equals

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Now the gauge pressure is given by

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3 years ago

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Hitman42 [59]

Answer:

Explanation:

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2 years ago

If a cars velocity is slowing down is it considered a positive or negative acceleration?

Natali [406]

Answer:

Negative

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2 years ago

A 20-kg child running at 1.4 m/s jumps onto a playground merry-go-round that has mass 180 kg and radius 1.6m. She is moving tang

Dominik [7]

Answer:

ωf = 0.16 rad/s

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(ASSUMING it is a uniform disk)

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44.8 = (51.2 + 230.4)ωf

ωf = 0.15909090...

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2 years ago