1.1 L of nitrogen dioxide were produced in the reaction seen below. How many liters of oxygen gas were used if the reaction occurred at STP?*
2N0 + 02 --> 2NOZ
O 22.4L
O 2.2L
O 0.55L
O 17.6L

One mole of zinc has a mass of 65.4 grams. approximately how many atoms of zinc are present in one mole of zinc? 32 × 1023 atoms 6 × 1023 atoms 66 atoms 65 atoms

Ahypothesis must be testable and falsifiable to be considered scientific a. trueb. false

When the chemicals iron sulfide (fes) and hydrochloric acid (hcl) are combined, bubbles appear from the mixture. 1. does the appearance of bubbles indicate a physical or chemical change? 2. why do the bubbles indicate this change? 3. what property is this?