A chemist requires 0.912 mol Na2CO3 for a reaction. How many grams does this correspond to?

19. Which is the most active nonmetal in the Periodic Table of the Elements? A) F B) C1 C) Na D) I

When a substance changes from a solid to a liquid, how does its mass change?

Balance the following redox equation in acidic solution using the smallest integers possible and select the correct coefficient for the H + (aq) ion. Cr2O72 - (aq) + Sn2 + (aq) → Cr3 + (aq) + Sn4 + (aq) a. 1 (no coefficient written) b. 2 c. 3 d. 4 e.

Damage to which of the following would disrupt the process of photosynthesis? A. chloroplast B. vacuole C. cell wall D. ribosome

How many isotopes of hydrogen exist in nature?

What is the difference between a solute and a solvent?

A 100 g sample of an unknown liquid absorbs 2000 j of heat energy, raising the liquid's temperature from 50 ◦ c to 70 ◦ c. what is the specific heat capacity of this liquid? no phase change took place.

How many moles are present in 1.51 x 10^23 molecules of HCl?

where do most earthquakes occur? A. within volcanoes where plates interact B. whar plates interact C. whar plates diverge D. at hot spots

Which question cannot be explained by chemistry? A. How does yeast make bread dough rise? B. Why does sugar dissolve faster in hot water? C. How does a convection oven cook food? D. Why do peeled apples turn brown in air?