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!
<span>Well it depends on percentage by what, but I'll just assume that it's percentage by mass.
For this, we look at the atomic masses of the elements present in the compound.
Cu has an atomic mass of 63.546 amu
Fe has 55.845 amu
and S has 36.065 amu
Since there are 2 molecules of Sulfur for each one of Cu and Fe, we'll multiply the Sulfur atomic weight by 2 to obtain 72.13 amu
So we have not established the mass of the compound in amus
63.546 + 55.845 + 72.13 = 191.521
That is the atomic mass of Chalcopyrite. and Iron's atomic mass is 55.845
So to get the percentage, or fraction of iron, we take 55.845 / 191.521
Which comes out to 29.15% by mass
Mass of the sample is not needed for this calculation, but since the question mentions it I would go ahead and check if the question isn't also asking for the mass of Iron in the sample as well, in which case you just find the 29.15% of 67.7g</span>
To determine the amount of a substance in units of moles from units of grams, we need to determine the molar mass of the substance. <span>The </span>molar mass<span> is the </span>mass<span> of a given chemical element or chemical compound (g) divided by the amount of substance (mol). For CuF2, the molar mass </span><span>101.543 g/mol. We calculate as follows:
100.0 g CuF2 ( 1 mol / 101.543 g) = 0.98 mol CuF2</span>
Answer : The final temperature of the copper is, 
Solution :
Formula used :

where,
Q = heat gained = 299 cal
m = mass of copper = 52 g
c = specific heat of copper =
= final temperature = ?
= initial temperature = 
Now put all the given values in the above formula, we get the final temperature of copper.


Therefore, the final temperature of the copper is, 