Answer:
Heat given off was -34.34kJ
Explanation:
Mass of iron bar = 869g
Initial temperature (T1) = 94°C
Final temperature (T2) = 5°C
Specific heat capacity of iron (c) = 0.444J/g°C
Heat energy (Q) = Mc∇T
Q = heat energy
c = specific heat capacity
∇T = change in temperature
M = mass of the substance
Q = mc∇T
∇T = T2 - T1
Q = Mc(T2 -T1)
Q = 869 * 0.444 * (5 - 94)
Q = 385.836 * -89
Q = -34339.404J
Q = -34.34kJ
The heat given of was -34.34kJ
First gap is BY USING MAGNETS
2nd is ELECTROLYSIS
3rd is EVAPORATION
Because fluorine has a higher electronegativity
Answer:
Various limitations of Mendeleev's periodic table are:-
Position of hydrogen - he couldn't assign a correct position to hydrogen as it showed properties of both alkali and halogens .
Position of isotopes - he considered that the properties of elements are a function of their atomic masses. Hence isotopes of a same element couldn't be placed.
In the d-block , elements with lower atomic number were placed before higher atomic number.
Explanation:
Answer:
0.098 moles
Explanation:
Let y represent the number of moles present
1 mole of Ba(OH)₂ contains 2 moles of OH- ions.
Hence, 0.049 moles of Ba(OH)2 contains y moles of OH- ions.
To get the y moles, we then do cross multiplication
1 mole * y mole = 2 moles * 0.049 mole
y mole = 2 * 0.049 / 1
y mole = 0.098 moles of OH- ions.
1 mole of OH- can neutralize 1 mole of H+
Therefore, 0.098 moles of HNO₃ are present.
