# What element has a mass number of 90?

Thorium

What is thorium's atomic mass?

232.03806 u

What is the mass number of an atom that contains 90 protons 144 neutrons and 90 electrons? #90 – Thorium – Th.

### What element has a mass number of 80?

mercury

What is the mass number in periodic table?

The mass number (represented by the letter A) is defined as the total number of protons and neutrons in an atom. Consider the table below, which shows data from the first six elements of the periodic table. Consider the element helium. Its atomic number is 2, so it has two protons in its nucleus.

### How do we find atomic mass?

To calculate the atomic mass of a single atom of an element, add up the mass of protons and neutrons. Example: Find the atomic mass of an isotope of carbon that has 7 neutrons. You can see from the periodic table that carbon has an atomic number of 6, which is its number of protons.

### How much is thorium a gram?

What is the cheapest source of thorium ? The best I could find is 6129\$ per gram for 0.22mm diameter wire, 1 meter long 99.95% purity (0.44536 grams) or 1164.50\$ per gram for 50x50x0.

### Why are there no thorium reactors?

Thorium-based reactors are safer because the reaction can easily be stopped and because the operation does not have to take place under extreme pressures. Compared to uranium reactors, thorium reactors produce far less waste and the waste that is generated is much less radioactive and much shorter-lived.

### How much does uranium cost?

Uranium purchases and prices Nearly 10% of the 40 million pounds U3O8e delivered in 2018 was U.S.-origin uranium at a weighted-average price of \$45.26 per pound. Foreign-origin uranium accounted for the remaining 90% of deliveries at a weighted-average price of \$38.11 per pound (Table 2).

### Where is uranium found?

Uranium ore deposits are economically recoverable concentrations of uranium within the Earth’s crust. Uranium is one of the more common elements in the Earth’s crust, being 40 times more common than silver and 500 times more common than gold. It can be found almost everywhere in rock, soil, rivers, and oceans.

### Where can I find thorium ore?

Thorium Ore is an ore which generates naturally in the world upon creation. It can also be found in Strange Crates and Scarlet Crates. Its associated bar can be made into a variety of useful early game tools and weapons. It can be mined with a Iron Pickaxe or better.

### How is Protactinium obtained?

Source: Protactinium occurs naturally in minute amounts (up to 3 parts per million) in uranium ores. Protactinium can also obtained as a by-product of uranium processing. Isotopes: Protactinium has 27 isotopes whose half-lives are known, with mass numbers 212 to 238. Protactinium has no stable isotopes.

### Is thorium flammable?

Nearly 100% of thorium found on Earth is thorium-232, which is only slightly radioactive because it has such a long half-life. Thorium is chemically reactive and is attacked by oxygen, hydrogen, the halogens and sulfur.

### What has a mass number of 65?

Explanation: Zinc, which has 30 protons, has a mass number of 65.39 amu. This means zinc has 30 protons and around 35 to 36 neutrons, depending on various isotopes that may form. Copper has an isotope with a mass number of 65, which is called copper-65.

### What are the mass number of the first twenty element?

Chemistry : List of Periodic Table Elements Sorted by: Atomic number No. Atomic Weight Name 17 35.453 Chlorine 18 39.948 Argon 19 39.098 Potassium 20 40.078 Calcium