Find the moles of CaO
divide mass (2.0g) by the RFM which is 56 (Ca is 40 add that to O which is 16 making 56) this gives 0.0356 moles.
Find the theoretical mass by multiplying the moles of CaO (which is 0.0356 as there are no balancing number making the ratio 1:1) by the RFM of Ca(OH)2 which is 74 (40+16+16+1+1)
74 (Ca(OH)2 RFM) x 0.0357 (CaO moles) = 2.6g which is the theoretical mass of Ca(OH)2
Find percentage yield by dividing the actual mass of Ca(OH)2 by the theoretical and then x100 this Should give you 82.3%
Answer:
ΔH° = + 6.2 kJ
Explanation:
Fe₂O₃(s) + 3CO(g) –––––> 2 Fe(s) + 3 CO₂(g); ΔH° = –26.8 kJ ......... ( 1 )
FeO(s) + CO(g) –––––> Fe(s) + CO₂(g); ΔH° = –16.5 kJ .........( 2 )
Multiplying equation ( 2 ) by 2 and subtracting it from ( 1 )
Fe₂O₃(s) + 3CO(g) -2 FeO(s) - 2CO(g) ––> 2 Fe(s) + 3 CO₂(g) - 2Fe(s) - 2CO₂(g) ΔH° = –26.8 kJ - ( 2 x –16.5 kJ )
Fe₂O₃(s) + CO(g) -2 FeO(s)––> CO₂(g) ΔH° = –26.8 kJ + 33 kJ
Fe₂O₃(s) + CO(g) ––>2 FeO(s) +CO₂(g) ΔH° = + 6.2 kJ
Required ΔH° = + 6.2 kJ Ans .
Answer:
Percentages are used widely and in many different areas. For example, discounts in shops, bank interest rates, rates of inflation and many statistics in the media are expressed as percentages. Percentages are important for understanding the financial aspects of everyday life.
Explanation:
Answer:
²⁵₁₁Na⁺
Explanation:
Details about the atom:
Number of electrons = 10 electrons
Number of neutrons = 14 neutrons
Number of protons = 11 protons
The atomic number of an atom is a good indicator of the type of atom we have been given.
From the subatomic particles, the number of protons is the same as the atomic number.
Since the number of protons is 11, its atomic number will be 11.
The element with atomic number 11 is sodium, Na.
To write a complete notation, we also need the mass number;
Mass number = number of protons + number of neutrons
Mass number = 11 + 14 = 25
The charge on the atom:
Charge = Number of protons - number of electrons = 11 - 10 = 1+
The element in isotopic notation is given as;
²⁵₁₁Na⁺
It is fluorescence
That means light reflecting
