((12g/mol)/(28.01g/mol))*100% = 42.84%
Check the boxes next to events or trends that first
occurred in science from about 1700.
X Darwin published his theory of natural selection.
-Darwin published his work in 1859.
X Archimedes described the principle of the lever.
-Archimedes discovered this during the third century BC
(300-201 BC)
/ Scientific societies and academies were formed.
-These were formed around 1789
X The double-helix structure of DNA was determined.
<span> -IT was discovered
in 1953 by James Watson and Francis Crick.</span>
X Copernicus proposed a Sun-centered universe.
<span>-It was proposed in the 16th century.</span>
X Continental drift was explained by the theory of plate
tectonics.
<span> -It was proposed
at around 1910 till 1950 but was accepted at 1960. </span>
X The Earth was proven to be spherical.
-It was argued at around 384-322 BC.
Answer:
pH measures ratio of H+ ions to OH- ions of substances
pOH measures ratio of OH- ions to H+ ions of substances
Explanation:
pH is a scale which measures the ratio of H+ ions to OH- ions to identify how acidic or basic a substance is. This is because acidic substances have high amounts of H+ ions and low amounts of OH- ions, and therefore have a higher ratio of H+ to OH- ions. (And vice versa for bases, low H+ to OH- ratio) On a pH scale, acidic substances have a pH of 0 to 7, water (neutral pH, not acidic nor basic) has a pH of 7, and bases have a pH of 7-14.
pOH is very similar to pH but measures the opposite: the ratio of OH- ions (indicative of a base) to H+ ions (indicative of an acid). Therefore the pH values are reversed on the scale: Basic substances have pOHs below 7, and acidic substances are above 7 on the pOH scale.
Fundamentally, these two scales measure the same thing is the same way, one just measures the ratio one way (H+:OH-), while the other measured them the other way (OH-:H+), resulting in flipped values on the scales:
pH: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
<---Acidic---> <------Basic------->
pOH: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
<----Basic----> <-----Acidic------->
Hope this helped!
Answer:
it's answer 2
Explanation:
magnets can only move metal
