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3 years ago

43.0 + 50.0 + 16.0= please answer with right amount of significant figures

Chemistry

1 answer:

zzz [600]3 years ago

8 0

Answer:

109.0

Explanation:

When adding or subtracting values, you must round your answer to the same "place" as the measurement with its last significant figure furthest to the left.

That is, you round off to the same number of decimal places as the measurement with the fewest decimal places.

43.0

50.0

+16.0

109.0

In each measurement, the “0” is the significant figure furthest to the left, so you round off the number to the “tenths" place. That's the last column that the measurements share.

109.0 → 109.0 (rounded to the “tenths” place)

In other words, you do not round off, and the sum has four significant figures.

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Explanation:

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3 years ago

Which of the following statements regarding alpha particles are true? Check all that apply.a. Alpha particles have a mass number

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Answer:

The only true statement is:

a. Alpha particles have a mass number of 4

Explanation:

Alpha particles are radiactive particles equivalent to a helium nucleus, so they have two protons and two neutrons.

Hence, alpha particles, α, are represented as:

⁴₂He

The superscript 4 to the left of the chemical symbol is the mass number: 2 protons + 2 neutrons = 4

The subscript 2 to the left of the chemical symbol is the atomic number: 2 protons = 2.

Hence, the statement "a. Alpha particles have a mass number of 4" is true.

As for the other statements, you have:

b. Alpha particles have a nulear charge of +1: false

Since, these particles are the nucleous of the helium atom, the nuclear charge equals the number of protons of this atom: +2. Hence, the statement is false.

c. Alpha particle formation is accompanied by the conversion of a proton into a neutron and d. Alpha particle formation is accompanied by the conversion of a neutron into a proton. (both false)

The conversion of a protons into a neutrons and the conversion of a neutron into a proton are product of other kind of radiactive desintegrations.

The conversion of a proton into a neutron involves the emission of a positron ( particle with same mass as the electron but positive charge) from the nucleus, which is represented as ⁰₊₁β.

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3 years ago

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GrogVix [38]

Answer:

The answer to the question is

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To solve the question we list out the known variables first

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taking moments about one of the support with Suki between the end of the beam and the support we have

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Answer:

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Lera25 [3.4K]

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