How are a mold and cast related?

Which of the following is the composition of an isotope of calcium (atomic number 20) ?

For the following hypothetical reaction: 3A+9B-->5C How many moles of B will you need to convert 2 moles of A into as many moles of C as possible? Enter just the number; not the number and units

What type of substance slows down a chemical reaction? A. inhibitor B. enzymes C. catalyst D. endotherm

A roast was cooked at 325 °F in the oven for 4 hours. The internal temperature rose from 32 °F to 145 °F. What was the average rise in temperature per hour?

What is the result of boiling the impure product with too much solvent and then cooling on ice?

What are some differences between insect larvae and worms?

Suppose that 100 grams of water at 50.0°C is placed in contact with 200 grams of iron at 30.0°C. The final temperature is 46.5°C. The specific heats of water and iron respectively, are 4.18 and 0.45 joules per gram times Celsius.

What type of overall charge, if any, does the balloon in Diagram B have? Explain how you determined your answer.

Move deep below the ocean's surface

The Ka of an acid is 1.3 x 10^-7. Based on the Ka and its relationship with Kw, what is the value of Kb? Use KaKb=Kw 1.3 x 10^-21 7.7 x 10^-15 1.3 x 10^-14 7.7 x 10^-8