Answer:
burning wood be a chemical change because it wouldn’t be able to go back to its original form. A physical change would be a broken pencil. The pencil is still a pencil, it’s just a physical change.But if it were burned it would be a chemical change.
Explanation:
Answer:
MARK AS BRAINLIEST
Explanation:
Boron trifluoride only has six valence electrons and is one of the relatively rare second period covalent molecules that disobeys the octet rule. There are three bonded groups and so no lone pairs. Six electrons implies three electron pairs and therefore a trigonal geometry.
Answer:
3.4 M
Explanation:
M = grams/molar mass = ans./volume(L)
M = 919/180 = ans./1.5
The reaction that should be followed is
Na2SO4 + C<span>a(NO3)2 --> CaSO4 + 2NaNO3</span>
first calculate the limiting reactant
mol Na2SO4 = 0.075 L (<span>1.54×10−2 mol / L) = 1.155x10-3 mol
mol Ca(NO3)2 = 0.075 L (</span><span>1.22×10−2 mol / L) = 9.15x10-4 mol
so the limiting reactant is the Ca(NO3)2
so all of the Ca2+ will be precipitated, percentage unprecipitated = 0.00 % </span>