All categories

3 years ago

How can scientist describe the arrangement of electrons in an atom?

Chemistry

1 answer:

Delicious77 [7]3 years ago

8 0

Answer:

The electrons in an atom move around the nucleus in regions known as electron shells.

You might be interested in

An organic compound is 61.5% C, 2.56% H and 35.9% N by mass. 2.00 grams of this gas is entered into a 300.0 mL flask and heated

pashok25 [27]

Answer:

C₄H₂N₂

Explanation:

First we calculate the moles of the gas, using PV=nRT:

P = 2670 torr ⇒ 2670/760 = 3.51 atm

V = 300 mL ⇒ 300/1000 = 0.3 L

T = 228 °C ⇒ 228 + 273.16 = 501.16 K

3.51 atm * 0.3 L = n * 0.082atm·L·mol⁻¹·K⁻¹ * 501.16 K

n = 0.0256 mol

Now we calculate the molar mass of the compound:

2.00 g / 0.0256 mol = 78 g/mol

Finally we use the percentages given to calculate the empirical formula:

C ⇒ 78 g/mol * 61.5/100 ÷ 12g/mol = 4

H ⇒ 78 g/mol * 2.56/100 ÷ 1g/mol = 2

N ⇒ 78 g/mol * 35.9/100 ÷ 14g/mol = 2

So the empirical formula is C₄H₂N₂

6 0

3 years ago

A reaction has activation energy of 85kjper mol. What is the effect on the rate of raising the temperature from 20degree to 30 d

DENIUS [597]

Answer: The rate increases 3 times on raising the temperature from 20degree to 30 degree

Explanation:

According to Arrhenius equation with change in temperature, the formula is as follows.

$ln \frac{k_{2}}{k_{1}} = \frac{-E_{a}}{R}[\frac{1}{T_{2}} - \frac{1}{T_{1}}]$

where $k_2$ = rate constant at temp $T_2$

$k_1$ = rate constant at temp $T_1$

$E_a$ = activation energy

R= gas constant

$T_1$ = temperature = $20^0C=(20+273)K=293K$

$T_2$ = temperature = $30^0C=(30+273)K=303K$

$ln \frac{k_{2}}{k_{1}} = \frac{-85\times 1000J/mol}{8.314J/Kmol}[\frac{1}{303} - \frac{1}{293}]$

$ln \frac{k_{2}}{k_{1}}=1.15$

$\frac{k_{2}}{k_{1}}=3$

Thus rate increases 3 times on raising the temperature from 20degree to 30 degree

3 0

3 years ago

Pls help! Polonium has a large, unstable nucleus. Through which process is it most likely to become stable?

Stella [2.4K]

The process through which Polonium is most likely to become stable is: B. alpha decay.

An unstable element refers to a chemical element that lose particles because its nucleus contain an excess of internal energy (neutron or proton).

This ultimately implies that, an unstable element is radioactive in nature.

In Science, some examples of an unstable element are:

Tritium.

Bismuth-209 .

Xenon.

Polonium.

Polonium is a chemical element with a large, unstable nucleus.

Basically, the most stable isotope of Polonium is Polonium-209, which typically undergoes an alpha decay to form lead-205 and the emission of an alpha particle.

⇒ $^{209}_{84}Po$ ----> $^{205}_{82}Pb \;+\; ^{4}_{2}\alpha$