What is the half-life of a 0.5 g sample of radioisotope that decayed to 0.125 g in 9.6 min?

24. Write the formula for the compound barium oxide.

If you remove one neutron from helium, the remainder is what element?

What does the author do to build understanding of the distance between Earth and this black hole? A They describe how long it would take a space ship traveling near the speed of light to reach it from Earth.

The goal of this experiment is to separate a mixture of two unknown compounds into individual components and to identify the compounds. Answer the questions below. More than one answer may be possible.

in an accident a solution containing 2.5 kg of nitric acid was spilled. Two kilograms of Na2CO3 was quickly spread on the area and CO2 was released by the reaction. was sufficient NaCO3 used to neutralize all of the acid?

Based on the passage, where in the United States would a physician encounter the most cases of SAD?

Draw the alkyne formed when 3,4-dichloroheptane is treated with an excess of strong base such as sodium amide

A penny has a mass of 2.50g and the moon has a mass of 7.35 X 10^22 Use this information to answer the questions below. Be sure your answers have the correct number of significant digits.

If a car tire has a diameter of 3232 inches, what is the approximate circumference of the tire?

9) Bettina spoke into a microphone during the school play to increase the sound of her voice so the audience could hear her speak.