All categories

3 years ago

What is an atomic number? An atomic mass?

Chemistry

2 answers:

Svetradugi [14.3K]3 years ago

8 0

Answer:

Atomic number

The number of protons in the nucleus of an atom.

Atomic Mass

The mass of an atom of a chemical element expressed in atomic mass units.

mrs_skeptik [129]3 years ago

4 0

Answer:

The atomic number is the number of the elements inside the periodic table and the mass is the weight or a number under the elements.

Explanation:

Correct me if I am wrong

You might be interested in

A syringe initially holds a sample of gas with a volume of 285 mL at 355 K and 1.88 atm. To what temperature must the gas in the

Ivahew [28]

<u>Answer:</u> The temperature to which the gas in the syringe must be heated is 720.5 K

<u>Explanation:</u>

To calculate the volume when temperature and pressure has changed, we use the equation given by combined gas law.

The equation follows:

$\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}$

where,

$P_1,V_1\text{ and }T_1$ are the initial pressure, volume and temperature of the gas

$P_2,V_2\text{ and }T_2$ are the final pressure, volume and temperature of the gas

We are given:

$P_1=1.88atm\\V_1=285mL\\T_1=355K\\P_2=2.50atm\\V_2=435mL\\T_2=?K$

Putting values in above equation, we get:

$\frac{1.88atm\times 285mL}{355K}=\frac{2.50atm\times 435mL}{T_2}\\\\T_2=\frac{2.50\times 435\times 355}{1.88\times 285}=720.5K$

Hence, the temperature to which the gas in the syringe must be heated is 720.5 K

8 0

3 years ago

What is the radius of a hydrogen atom whose electron is bound by 0.544 ev? express your answer with the appropriate units?

insens350 [35]

First, we need to calculate the principal quantum number n for this electron, using the equation:
E = (-13.60 eV) / (n x n)
where E is the energy that is used to bound the electron (here, E = - 0.544 eV).
- 0.544 eV = (-13.60 eV) / (n x n)
n x n = (- 13.60 eV) / (- 0.544 eV)
n x n = 25
n = 5

The orbital radius that is equal to the radius of a hydrogen atom is calculated using the equation:
r = 0.053 nm x n x n
r = 0.053 nm x 5 x 5
r = 0.053 nm x 25
r = 1.325 nm

6 0

3 years ago

Before a bond breaks in a chemical reaction, what happens

Assoli18 [71]

They have to form a chemical bond in order to brake them down first

8 0

3 years ago

PLS help

viktelen [127]

Answer:

d . Sc2O5

Explanation:

Hello,

In this case, when forming oxides from a metal and oxygen, for us to find out each element's subscript, we must exchange them as shown below, considering +5 for scandium:

$Sc^{+5}_2O^{-2}_5$