An isotope of radon has 86 protons and 137 neutrons. What is the mass number of this isotope?

Scientists have collected and studied data showing that acid rain is cause by which gas? carbon monoxide sulfur dioxide nitrogen dioxide carbon dioxide

How many unpaired electrons are present in the ground state of a phosphorus atom? a. 3 0.0

A how many hydrogen atoms are in an acyclic alkane with 7 carbon atoms?

Which of the following for an object should be known to calculate its density? a) the heat present in it b) the amount of matter in it c) the force of gravity acting on it d) space between object and another object

The first element of family 16

What is the molar mass of the following substance : Cs2CO3

What does the velocity of a wave describe

Sulfur (S) has 16 protons and 16 neutrons. How many electron shells does an element of sulfur have?

Which one of the following statements about orbital energies is incorrect? A) The energy of a given orbital increases as the nuclear charge Z increases. B) In many-electron atoms the energy of an orbital depends on both n and l.

When solid lead (II) sulfide ore burns in oxygen gas, the products are solid lead (II) oxide and sulfur dioxide gas.? A. write the balanced equation B. how many grams of oxygen are required to react with 29.9 grams of lead II sulfide? C.