Which is evidence that scientists use to support the big bang theory?
a.
there is constant cosmic background radiation.
b.
galaxies are moving toward each other.
c.
a loud explosion can be heard in the radio frequencies everywhere in the universe.
d.
hydrogen and helium are the most abundant elements in the universe.

Answer asap need it by wednesday morning carry out the following calculations on ph and ka of from data. i. calculate the ph of 0.02m hcl ii. calculate the ph of 0.036m naoh iii. calculate the ph of 0.36m ca(oh)2 iv. calculate the ph of 0.16m ch3cooh which has ka = 1.74 x 10-5 mol dm-3 v. calculate ka for weak acid ha which has a ph of 3.65 at 0.30m concentration vi. calculate the ka of a solution made by mixing 15.0 cm3 0.2m ha and 60.0 cm3 0.31m a-. [ph= 3.80] vii. calculate the ph of a solution made by mixing 15.0 cm3 0.1m naoh and 35.0 cm3 0.2m hcooh. [ka = 1.82 x 10-4 m]

Question 3(multiple choice worth 4 points) (04.04 lc) what does it mean when an element is reduced? it empties a valance shell, reducing its atomic radius. it gains electrons, reducing its overall charge. it increases electronegativity, reducing its ability to bond. it loses electrons, reducing its electron number.

In vapor-liquid equilibrium in a binary mixture, both components are generally present in both phases. how many degrees of freedom are there for such a system? the reaction between nitrogen and hydrogen to form ammonia occurs in the gas phase. how many degrees of freedom are there for this system? steam and coal react at high temperatures to form hydrogen, carbon monoxide, carbon dioxide, and methane. the following reactions have been suggested as being involved in the chemical transformation: