What is the number of known elements?

Naphthalene is a soft covalent solid that is often used in mothballs. Its molar mass is 128.18 g/mol and it contains 93.75% carbon and 6.25% hydrogen. Determine the molecular formula of napthalene from this data.

What was the principal use of calcium sulfate in hospitals

What is freshly prepared feso4 used in ghe brown ring test

Eva pumps up her bicycle tire until it has a gauge pressure of 413 kilopascals. If the surrounding air is at standard pressure, what is the absolute pressure in the bicycle tire? A. 33.9 kPa B. 49.7 kPa C. 312 kPa D. 514 kPa

To treat certain forms of cancer, physicians may choose to irradiate the body with high-energy radiation. Why does this therapy work?

Hydrogen is an element with two naturally occurring isotopes: 2 H and 3 H. This means that 2 H, which has a mass number of 2, has fewer than 3 H, which has a mass number of 3. True/False

C₂H₂ + O2 - CO₂ + H₂ How many moles of oxygen are necessary to react completely with 4.0 moles of propane (CH) ?

What are the two main classifications of energy resources?

A liquid is heated and a solid forms at the bottom of the beaker. Is this a physical or chemical change?

How to predict the formula of an ionic compound based on the charges of the ions?