Question #1
Potasium hydroxide (known)
volume used is 25 ml
Molarity (concentration) = 0.150 M
Moles of KOH used
0.150 × 25/1000 = 0.00375 moles
Sulfuric acid (H2SO4)
volume used = 15.0 ml
unknown concentration
The equation for the reaction is
2KOH (aq)+ H2SO4(aq) = K2SO4(aq) + 2H2O(l)
Thus, the Mole ratio of KOH to H2SO4 is 2:1
Therefore, moles of H2SO4 used will be;
0.00375 × 1/2 = 0.001875 moles
Acid (sulfuric acid) concentration
0.001875 moles × 1000/15
= 0.125 M
Question #2
Hydrogen bromide (acid)
Volume used = 30 ml
Concentration is 0.250 M
Moles of HBr used;
0.25 × 30/1000
= 0.0075 moles
Sodium Hydroxide (base)
Volume used 20 ml
Concentration (unknown)
The equation for the reaction is
NaOH + HBr = NaBr + H2O
The mole ratio of NaOH : HBr is 1 : 1
Therefore, moles of NaOH used;
= 0.0075 moles
NaOH concentration will be
= 0.0075 moles × 1000/20
= 0.375 M
Solution: Sentence D is a scientific statement.
Scientific statement is a statement that defines the science behind any situation. There should be any experimental result or observation to state any scientific statement. Also, the statement should be accepted by considering other scientific aspects.
Here, statement A can not be a scientific statement as different aromas of cooked food are liked by different people. Any one can find aroma of cooked food in copper better than the ceramic pot.
Thus, the statement can be proved wrong easily.
Statement B can not be a scientific statement as people can find the taste of normal water (without ice cubes) better than the ice cold water.
Statement C is not a scientific statement as there is no science behind watching baseball or ice hockey, it depends on the liking of today's people.
Statement D is a scientific statement because this can be scientifically proved.
Answer:
An elementary particle that is identical with the nucleus of the hydrogen atom, that along with the neutron is a constituent of all other atomic nuclei, that carries a positive charge numerically equal to the charge of an electron.
Example:
The nucleus of a hydrogen atom or the H+ ion is an example of a proton. Regardless of the isotope, each atom of hydrogen has 1 proton; each helium atom contains 2 protons; each lithium atom contains 3 protons and so on.
Answer:
The mole ratio of the cation and the anion in a precipitate is a simple fraction. ( im sorry if this dosent help a lot.)
Explanation:
Density=mass/ volume so you solve for volume and get 461.96 mL
