Answer:
3.0 moles.
Explanation:
- It is a stichiometry problem.
- The chemical reaction of reacting hydrogen with oxygen to produce water is:
<em>H₂ + 1/2 O₂ → H₂O.</em>
- It is clear that <em><u>1.0 mole of H₂</u></em> reacts with 0.5 mole of O₂ to produce <u><em>1.0 mole of water</em></u>.
- The ratio of the reacting hydrogen to the produced water is 1:1.
∴ The number of moles of water created from reacting 3.0 moles of hydrogen completely with excess oxygen = 3.0 moles.
As water freezes its molecules move farther apart. As when water freezes , Its move farther apart .
And the cause of this movement is hydrogen bond that is formed among the surrounding water molecules that causes water molecules to move apart. So as water freezes its molecules move farther apart, it is the correct answer .
Answer:
To ensure provide and reliable data
Explanation:
Calibration ensures precise repeatable performance while preventing pipetting errors. Just the way measurement standards are established to distinguish valid and invalid processes, pipette calibration standards are designed to ensure the best pipette accuracy.
Answer
a
Explanation:
While the Arrhenius definition of a base agrees with this statement, the Bronsted-Lowry and Lewis definitions don't. Under Bronsted-Lowry, a base is anything that can accept a proton (ex// NH3). Under lewis, it is anything that can donate an electron (ex// Cl-).
Bases are usually bitter and turn red litmus paper blue, and are slippery.
