Which of these substances is not an element?

a. water

b. hydrogen

c. aluminum

d. iron

What is an example of reactivity? O A. Sugar dissolving O B. Brass tarnishing O c. Rain falling O D. Water freezing

There are four major methods of purification in the chemistry laboratory. Which of the given techniques is not one of the four most common methods for separation and purification? distillation recrystallization extraction chromatography sublimation

If 36.0 g of so2 is produced, what is the percent yield for the reaction?

The lewis dot structure for water, shown above, has how many lone-pair electron groups?

What does a number pyramid tell you about an ecosystem? The biomass of each trophic level. The number of organisms in each trophic level. The lifespan of organisms in each trophic level. The energy transfer between trophic levels.

0.402 L = 402 mL 0.0202 L = 20.2 mL 3.6 L = 360 mL 11.1 L = 11,100 mL

Which is one possible way the digestive system works together with other body system

Can anyone tell me how to balance chemical equations

Nomadic people received income from where

How many milliliters of 0.755 m h2so4 solution is needed to react with 55.0 ml of 2.50 m koh solution? given: 2 koh (aq) + h2so4 (aq) → 2 h2o (l) + k2so4 (aq) ?