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:
sodium sulfate
Explanation:
For naming an ionic compound with polyatomic anion, the metal is written first using its element name followed by name of the polyatomic anion. Therefore, the compound with Na+Na+ cation and SO2−4SO42− anion is named as sodium sulfate.
Answer:
1.05 V
Explanation:
Since;
E°cell= E°cathode- E°anode
E°cathode= -0.40 V
E°anode= -1.45 V
E°cell= -0.40-(-1.45) = 1.05 V
Equation of the process;
2Zr(s) + 4Cd^2+(aq) ---->2Zr^4+(aq) + 4Cd(s)
n= 8 electrons transferred
From Nernst's equation;
Ecell = E°cell - 0.0592/n log Q
Ecell= E°cell - 0.0592/8 log [0.5]/[0.5]
Since log 1=0
Ecell= E°cell= 1.05 V
Answer:
Bond points will go astray from their perfect values agreeing to the run the show that solitary sets repulse other electrons more unequivocally than holding sets. In spite of the fact that solitary sets are clearly littler than molecules, they got to be closer to the core of an molecule than a holding combine.
1.curium ( 1944 Marie and Pierre Curie
<span>2.einsteinium ( Albert Einstein) </span>
<span>3.fermium (1953 Enrico Fermi) </span>
<span>4.mendelevium (1955 Dmitri Mendeleev, who devised first Periodic Table) </span>
<span>5.nobelium ( 1957 Alfred Nobel) </span>
<span>6.niobium (1801 Niobe/ daughter of Tantalus) </span>
<span>7.samarium (1879 Samarski, a Russian engineer) </span>
<span>8.titanium (1791 Greek mythology, Titans, first sons of earth) </span>
<span>9.thorium ( 1819 named after Thor of course !!!:) ) </span>
<span>10.tantalum ( 1802 Tantalus of Greek mythology) pick which ever best that your more into hope this helped you alot:/</span>
