A fictitious element X is composed of 10.0 percent of the isotope 55X, 20.0 percent of the isotope 56X, and 70.0 percent of the isotope 57X. Calculate the weighted atomic mass of element X to the nearest tenth.

when 102.4 grams of sodium produces calcium by reacting with calcuim iodide the reaction also produces sodium iodide. How many atoms of calcium will be formed?

Based on its chemical formula, which of the following substances is an organic compound

Molecules in a sample of NH3 (l) are held closely together by intermolecular forces (1) existing between ions (2) existing between electrons (3) caused by different numbers of neutrons (4) caused by unequal charge distribution

Below is the correct formula unit for Sodium Chloride NaCl2 A. True <- - I believe this is correct. B. False

You add two substances together in a sealed bag and a chemical reaction happens. The mass before the reaction was 167 g. What was the mass after the reaction? Why?

An atom has an atomic number of 9 a mass number of 19 and an electron configuration of 2-6-1 explain why the number of electrons in the second and third shells shows that this is in an excited state

How can a chemical reaction be sped up? Pack in more of the reactant to increase the_.

How does a mixture of benzoic acid and benzaldehyde can be isolated separately by extractions?

What is a compound? a) a combination of two or more substances that are not chemically combined b) a combination of two or more elements that are combined in a certain ratio

A gas has a volume of 75mL at a pressure of 200.0 kPa. What will be the new volume be in mL if the pressure is decreased to 60.0 kPa in sig figs