# What is the mass number of an element that contains 19 protons 19 electrons and 20 neutrons?

## What is the mass number of an element that contains 19 protons 19 electrons and 20 neutrons?

The element potassium’s atomic number is 19. Its relative atomic mass is 39.098. How many protons occur in a potassium atom?

### What element has 19 protons 19 electrons and 21 neutrons?

The number of neutrons tells us which isotope of potassium it is. Add the 19 (protons) to the 21 (neutons) and you get 40. So it’s Potassium 40.

READ:   How do you politely end an argument?

#### What is the mass number of an ion with 18 electrons 19 protons and 20 neutrons?

Because the mass number of an atom is the sum of proton number and neutron number of the atom. So, 18 + 20 = 38.

How do you find the mass number?

Together, the number of protons and the number of neutrons determine an element’s mass number: mass number = protons + neutrons. If you want to calculate how many neutrons an atom has, you can simply subtract the number of protons, or atomic number, from the mass number.

What element has an atomic mass of 19?

The Elements, sorted by Atomic Number

Atomic Number Symbol Atomic Mass (amu, g/mol)
16 S 32.06
17 Cl 35.453
18 Ar 39.948
19 K 39.0983

## What is the electron configuration for 39 19 K?

Fact box

Group 1 63.5°C, 146.3°F, 336.7 K
Block s 0.89
Atomic number 19 39.098
State at 20°C Solid 39K
Electron configuration [Ar] 4s1 7440-09-7
READ:   Is the jet interview hard?

### What element contains 19 electrons?

potassium
So if you look for potassium (symbol K in the periodic table), you will find that it has the atomic number of 19. This tells you that potassium has 19 protons and – since the number of protons is the same as the number of electrons- also 19 electrons.

#### What has 18 protons and 18 electrons and 19 neutrons?

Which ion would contain 19 electrons?

Element Protons Electrons
Potassium atom 19 19
Potassium ion 19 18
Sulfur atom 16 16
Sulfur ion 16 18

How do u find the mass of an element?

For any given isotope, the sum of the numbers of protons and neutrons in the nucleus is called the mass number. This is because each proton and each neutron weigh one atomic mass unit (amu). By adding together the number of protons and neutrons and multiplying by 1 amu, you can calculate the mass of the atom.

READ:   What is considered rich in New York?

What is the mass of an electron answer?

The rest mass of the electron is 9.1093837015 × 10−31 kg, which is only 1/1,836the mass of a proton.

## Who discovered fluorine 19?

In the early 19th century, scientists Andre-Marie Ampere, in France, and Humphry Davy, in England, corresponded about the possibility of a new element within the acid. In 1813, Davy announced the discovery of the new element and named it fluorine from Ampere’s suggestion.

### What does the atomic number 19 mean?

Potassium
Potassium is a chemical element with the symbol K (from Neo-Latin kalium) and atomic number 19. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives.