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3 years ago

19) The nuclear symbol of helium,

Chemistry

1 answer:

Amiraneli [1.4K]3 years ago

4 0

Answer:

Alpha particle

Explanation:

The helium symbol is also used to represent he alpha particles.

For example:

The americium with atomic wight 224 undergo alpha decay and produce

₉₃Np²³⁷ . The alpha particle emitted is also called helium nuclei. During this decay some gamma radiations also produce as a byproduct.

₉₅Am²²⁴ → ₉₃Np²³⁷ + ₂He⁴

Properties of alpha radiation:

Alpha radiations are emitted as a result of radioactive decay. The atom emit the alpha particles consist of two proton and two neutrons. Which is also called helium nuclei. When atom undergoes the alpha emission the original atom convert into the atom having mass number 4 less than and atomic number 2 less than the starting atom.

Alpha radiations can travel in a short distance.

These radiations can not penetrate into the skin or clothes.

These radiations can be harmful for the human if these are inhaled.

These radiations can be stopped by a piece of paper.

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Adding acid and and catching the solution that drains through.

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A colorless liquid has a molar mass of 60.01 g/mol. When the liquid was analyzed, it was 46.7% nitrogen and 53.3% oxygen. What i

MAXImum [283]

first we have to find the empirical formula of the compound

empirical formula is the simplest ratio of whole numbers of components making up a compound

for 100 g of the compound

N O

mass 46.7 g 53.3 g

number of 46.7 g/ 14 g/mol 53.3 g/ 16 g/mol

moles = 3.34 mol = 3.33 mol

divide by the least number of moles

3.34/3.33 = 1.00 3.33/ 3,33 = 1.00

therefore number of atoms are

N - 1

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mass of empirical unit - 14 g/mol + 16 g/mol = 30 g

molecular formula is actual composition of elements in the compound

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number of empirical units = molecular mass / empirical unit mass

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2 years ago

How many grams of Carbon are in sample of 400 grams of Co2?

RoseWind [281]

Answer:

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Explanation:

Given data:

Mass of carbondioxide = 400 g

Mass of carbon = ?

Solution:

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3 years ago

Select the keyword or phrase that will best complete each sentence. A Claisen reaction is a nucleophilic ____________ in which a

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Answer:

Substitution.

Explanation:

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2 years ago

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Gnesinka [82]

Answer:

The correct answer is option c.

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