A sample contains 2.2 g of the radioisotope niobium-91 and 15.4 g of its daughter isotope, zirconium-91. how many half-lives have passed since the sample originally formed?

What is the difference between a 1s orbital and a 2s orbital is that

On a summer day, you take a road trip through Chelan, WA, in a Tesla Model S. You start out at a temperature of 19°C in the morning, but the temperature in Chelan will reach a peak of 55°C. Each tire on your car holds 16.

3. With which temperature scale is temperature directly proportional to average kinetic energy? A. Celsius B Fahrenheit C. Kelvin D. centigrade 4. Which states of matter can flow? A. gases only B. liquids only C. gases and liquids only D.

Why is PCl3 called phosphorus trichloride

K12 chemistry unit assessment: chemical bonding, electrostatic forces in ionic bonds hold which of the following together? 1. He atoms in helium gas 2. Na + and Br - in NaBr 3. Fe atoms and localized electrons in iron

How many grams of CuSO4 are there in 100.0 g of hydrate? How many moles?

Which student is determining the atomic mass of sodium?

Ionic compounds can conduct electricity when dissolved in water or melted, because a. the ions are free to move. b. they have no ions to contribute to the solution. c. the ions are fixed in place. d. they have shared electrons.

What does the number next to the ion signify?

Write a molecular equation for the precipitation reaction potassium chloride and lead (II) acetate