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3 years ago

An atom or ion has 41 neutrons, 36 protons, and 36 electrons. Identify the element symbol, and determine the mass number

Chemistry

1 answer:

igor_vitrenko [27]3 years ago

5 0

Answer:

Element symbol: Kr.

Mass number: 77.

Charge : 0.

Explanation:

Hello,

In this case, since such substance has the same amount of protons and electrons we can infer it is an atom whose number of neutrons is defined by considering its atomic mass or mass number and atomic number which is actually equal to the number of protons and electrons (36):

$neutrons=atomic\ mass - atomic\ number$

In such a way, solving for the atomic mass we obtain:

$atomic\ mass=neutrons+ atomic\ number\\\\atomic\ mass=41+36=77$

It means that the element is krypton (Kr) as it has 36 electrons and protons so its charge is 0.

Best regards.

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The given question is incomplete. The complete question is :

In each row check off the boxes that apply to the underlined reactant. The underlined reactant acts as a... (check all that apply)

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here underlined is $HCH_3CO_2$

A. Brønsted-Lowry acid

B. Brønsted-Lowry base

C. Lewis acid

D. Lewis base

2. $BH_3(aq)+NH_3(aq)\rightarrow BH_3NH_3(aq)$

Here underlined is $NH_3$

A. Brønsted-Lowry acid

B. Brønsted-Lowry base

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A. Brønsted-Lowry acid

B. Brønsted-Lowry base

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Answer: 1. Brønsted-Lowry acid

2. Lewis base

3. Brønsted-Lowry base

Explanation:

According to the Bronsted Lowry conjugate acid-base theory, an acid is defined as a substance which donates protons and a base is defined as a substance which accepts protons.

According to the Lewis concept, an acid is defined as a substance that accepts electron pairs and base is defined as a substance which donates electron pairs.

1. $HCH_3CO_2(aq)+NH_3(aq)\rightarrow CH_3CO^{2-}(aq)+NH_4^+aq)$

As $HCH_3CO_2(aq)$ is donating a proton , it acts as a bronsted acid.

2. $BH_3(aq)+NH_3(aq)\rightarrow BH_3NH_3(aq)$

As $NH_3$ contains a lone pair of electron on nitrogen , it can easily donate electrons to $BH_3$ and act as lewi base.

3. $HNO_2(aq)+C_2H_5NH_2(aq)\rightarrow NO_2^-(aq) + C_2H_5NH_3^+(aq)$

As $C_2H_5NH_2(aq)$ is accepting a proton , it acts as a bronsted base.

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3 years ago

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garik1379 [7]

Answer:

526g is the mass of this sample

Explanation:

To solve this question we must, as first, find the <em>molar mass </em>of Al₂(Cr₂O₇)₃ using the periodic table. The molar mass is defined as the mass of this compound per mole. With this value we can find the mass in 0.750 moles as follows:

<em>Molar mass Al₂(Cr₂O₇)₃</em>

2Al = 2*26.98g/mol = 53.96g/mol

6 Cr = 6*51.9961g/mol = 311.9766g/mol

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53.96g/mol + 311.9766g/mol + 335.979g/mol

= 701.9156g/mol

The mass of 0.750 moles is:

0.750 moles * (701.9156g / mol) =

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2 years ago

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Answer:

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Explanation:

52. To obtain Methyl propanoate, CH3CH2COOCH3, we simply react propanoic, CH3CH2COOH and methanol, CH3OH together as shown below:

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Formic acid, HCOOH and ethanol, CH3CH2OH together as show below:

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Answer:

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3 years ago