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
Answer:
protactinium-234,
Explanation:
This is what happens when thorium-234 releases a W- boson, which then decays to an electron and an electron antineutrino.
Answer:
D. The relationship between volume and moles
Explanation:
Amedo Avogadro found the relationship between the volume of a gas and the number of molecules contained in the volume.
The law states that "equal volume of all gases at the same temperature and pressure contains the same number of molecules or moles".
Mathematically:
V ∝ n (P,T constant)
This is covalent network type of solid.
For example, silicon dioxide (SiO₂) is covalent network solid with covalent bonding.
Covalent network solid is a chemical compound (or element) in which the atoms are bonded by covalent bonds in a continuous network extending throughout the material.
Silicon(IV) oxide has continuous three-dimensional network of SiO₂ units and diamond has sp3 hybridization.
This solids do not have free electrons so they are good insulators.
They have strong covalent bonds, so they melt at extremely high temperature.
Other examples are quartz, diamond, and silicon carbide.
More about network solid: brainly.com/question/15548648
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