Answer:
See below
Step-by-step explanation:
(a) Shape
The formula for water is H-O-H.
The central O atom has four electron pairs around it. They try to get as far from each other as possible, so they point toward the corners of a tetrahedron.
Only two of the pairs have a hydrogen atom attached, so water has a bent shape. The H-O-H bond angle is about 104°.
(b) Chemical magnet
The O atom has a greater attraction than H for the shared electrons in the O-H bonds, so the electrons spend more time near the O.
This gives the O atom a partial negative charge (pink in the diagram) and the H atoms a partial positive charge (blue).
The water molecule acts like a chemical magnet because its negative end attracts the positive ends of other molecules, while its positive ends attract the negative ends of other molecules.
Answer:
So first thing to do in these types of problems is write out your chemical reaction and balance it:
Mg + O2 --> MgO
Then you need to start thinking about moles of Magnesium for moles of Magnesium Oxide. Based on the above equation 1 mole of Magnesium is needed to make one mole of Magnesium Oxide.
To get moles of magnesium you need to take the grams you started with (.418) and convert to moles by dividing by molecular weight of Mg (24.305), this gives you .0172 moles of Mg.
The theoretical yield would be the assumption that 100% of the magnesium will be converted into Magnesium Oxide, so you would get, based on the first equation, .0172 mol of MgO. Multiplying this by the molecular weight of MgO (24.305+16) gives us .693 g of MgO.
The percent yield is what you actually got in the experiment, and for this you subtract off the total mass from the crucible mass, or 27.374 - 26.687, which gives .66 g of MgO obtained.
Percent yield is acutal/theoretical, .66/.693, or 95.24%.
I'll let you do the same for the second trial, and average percent yield is just an average of the two trials percent yield.
Hope this helps.
Answer:
2. Full
Explanation:
A lunar eclipse occurs at a full moon when Earth is directly between the moon and the sun. During a lunar eclipse, Earth blocks sunlight from reaching the moon.
Hope this helps!!
The <span> the Brønsted-Lowry acid donates H⁻.
In this reaction Particle that loose H⁺ is A. NH4⁺ ion.</span>
The equilibrium constant (Kp) for the formation of the air pollutant nitric oxide (NO) in an automobile engine at 530 degree C is 2.9 x 10 to the minus eleventh
N2(g) + O2 (g) = 2 NO (g)
