Answer:
A. To focus on only those ions that form the precipitate
Explanation:
Net ionic equations cancel out the ions that appear on both sides of the reaction because they essentially don't participate in the reaction. This is very useful when dealing with redox reactions because are complicated enough without spectator ions being in the way, so they help focus on those ions that actually form the precipitate.
Key Terms
- Spectator Ions: an ion that does not take part in the chemical reaction.
- Net ionic equations: a equation where ions that appear on both sides are canceled out.
- Redox reaction: an oxidation-reduction reaction.
Answer:
The mechanical properties of urea formaldehyde resins may be improved by incorporating therein polyvinyl alcohol. The polyvinyl alcohol may be incorporated during pre-mixing, mid mixing, and/or post mixing of the resin components. Resins prepared using polyvinyl alcohol are particularly desirable in articles requiring improved mechanical strength and water resistance, as compared to similar resins prepared without the polyvinyl alcohol such as shingles.
7+8=15 es un cation ok ok ok ok
Conduction is particle to particle. Convection is by molecular motion. Radiation is energy that is transmitted in the form of rays or waves. C seems like the best answer.
Answer: In the exercise there are lost data, but I already found the exercise in a book
qsoot= 6.66e-18
no. electrons = approximately 42 electrons
Explanation:
msoot = 1.2e-12 kg
qcollector = 2e-06 C
rcollector = 0.1 m
The electric force must be equal to the weigth, so:
W=msoot*g (1)
Felec = k*qsoot*qcollector/r^2 (2)
equaling (1) and (2):
msoot*g = k*qsoot*qcollector/r^2 (3)
reorganizing the equation (3) and clear qsoot:
qsoot = (msoot*g*r^2)/(k*qcollector)
qsoot= 6.66e-18
no. electrons = qsoot / qelectron
no electrons = 41.6 electros (approximately 42 electrons)
