Which of the following best describes what happens in radioactive decay?

a. the nucleus emits particles and/or energy.

b. the electron cloud emits particles and/or energy.

c. the nucleus transfers particles and/or energy to the electron cloud.

d. the electron cloud transfers energy to the nucleus.

Determine the empirical formula of a compound containing 40.6 grams of carbon, 5.1 grams of hydrogen, and 54.2 grams of oxygen. in an experiment, the molar mass of the compound was determined to be 118.084 g/mol. what is the molecular formula of the compound? for both questions, show your work or explain how you determined the formulas by giving specific values used in calculations.

Which real-world scenarios below represent physical and chemical changes? -running a car -exploding fireworks -mixing water and powdered drink mix -combining oil and vinegar to make salad dressing -taking aspirin for a headache -diluting bleach with water-digesting dinner-spreading peanut butter on bread

The chart shows the bid provided by four contractors to complete a job. which contractor is the most cost-effective?