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2 years ago

Determine the element symbol, mass number, and charge for an atom or ion that has a 51 neutrons, 38 protons, and 36 electrons.

Chemistry

1 answer:

amid [387]2 years ago

3 0

Answer:

Strontium

Explanation:

To find the element, we need to know the atomic number. There is this rule in chemistry that says that the number of protons and the atomic number are the same. Since we know that there are 38 protons, the atomic number is also 38, leading us to Strontium. Sr -- element symbol.

The mass number is located below the element symbol on a periodic table. The mass number or the atomic mass for Strontium is 87.62 u.

Since there are an uneven amount of protons and electrons, let's subtract the number of electrons from the number of protons to find the difference. 38-36 = 2. (Also, protons are positive and electrons are negative, meaning there are more + than - in the ionic charge). Which means, the atom has a +2 ionic charge.

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Which compound is a polar molecule and has a linear geometry

kirill115 [55]

Answer:

Linear molecule is a molecule in which atoms are deployed in a straight line (under 180° angle). Molecules with an linear electron pair geometries have sp hybridization at the central atom. An example of linear electron pair and molecular geometry are carbon dioxide (O=C=O) and beryllium hydride BeH2.

Explanation:

6 0

2 years ago

Al agregar 150g de una sustancia X en un recipiente que sostiene que contiene agua hasta 50, el nivel del agua aumenta hasta 120

vovangra [49]

Answer:

2,14 g / ml

Explanation:

Sabemos que el volumen de una sustancia es igual al cambio de volumen del agua cuando el objeto en cuestión se sumerge en el agua.

Dado que el volumen original del agua = 50 ml

Volumen de agua después de sumergir el objeto = 120 ml

Masa del objeto = 150 g

Ahora,

Densidad = masa / volumen

Densidad = 150g / 120-50 ml

Densidad = 150/70 ml

Densidad = 2,14 g / ml

4 0

2 years ago

I NEED HELP QUICK! BRAINLIEST TO WHO IS RIGHT!

Travka [436]

Answer:

3rd option

Explanation:

3 0

2 years ago

The energy E of the electron in a hydrogen atom can be calculated from the Bohr formula: E = R_y/n^2 In this equation R_y stands

Katarina [22]

Answer:

The wavelength of the line in the emission line spectrum of hydrogen caused by the transition of the electron for the given energy levels is $5.23\times 10^{-5} m$

Explanation:

Given :

The energy E of the electron in a hydrogen atom can be calculated from the Bohr formula:

$E=\frac{R_y}{n^2}$

$R_y=2.18\times 10^{-18} J$ = Rydberg energy

n = principal quantum number of the orbital

Energy of 11th orbit = $E_{11}$

$E_{11}=\frac{2.18\times 10^{-18} J}{11^2}=1.80\times 10^{-20} J$

Energy of 10th orbit = $E_{10}$

$E_{10}=\frac{2.18\times 10^{-18} J}{10^2}=2.18\times 10^{-20} J$

Energy difference between both the levels will corresponds to the energy of the wavelength of the line which can be calculated by using Planck's equation.

$E'=E_{10}-E_{11}=2.18\times 10^{-20} J-1.80\times 10^{-20} J$

$=E'=0.38\times 10^{-20} J$

$\lambda =\frac{hc}{E'}$ (Planck's' equation)

$\lambda = \frac{6.626\times 10^{-34} Js\times 3\times 10^8 m/s}{0.38\times 10^{-20} J}$

$\lambda = 5.2310\times 10^{-5} m\approx 5.23\times 10^{-5} m$

The wavelength of the line in the emission line spectrum of hydrogen caused by the transition of the electron for the given energy levels is $5.23\times 10^{-5} m$

3 0

2 years ago

92dm3 of a gas dissolved in a solvent. How many moles is this?

Paul [167]

Assuming its at r. t.p and pressure
no. of moles = 96/24=4moles
altho some books will say that its 23.7dm3/mole but that doesnt really matter because its the process that matters

5 0

3 years ago