Answer:
Heat absorbed by water = 3985.26 j
Explanation:
Given data:
Mass of water = 75 g
Initial temperature = 20.0°C
Final temperature = 32.7°C
Specific heat of water = 4.184 j/g.°C
Heat absorbed by water = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 32.7°C - 20°C
ΔT = 12.7 °C
Q = 75 g ×4.184 j/g.°C ×12.7 °C
Q = 3985.26 j
<span>The correct formula for Beryllium phosphate is Be3(PO4)2
Beryllium has a charge of +2 and phosphate has a charge of -3. So to make the charge equal to zero, 3x +2 = 6, and 2 x-3 = -6
-6 + +6 = 0</span>
<span>According to octet rule, atoms with an atomic number less than 20 tend to combine with other atom such that both of these atoms have eight electrons in their valence shells, which gives them the same electronic configuration as that of noble gas.
However, there are few compound that donot obey octel rule. Among the elements mentioned above i.e. oxygen and helium obeys octet rule.
In case of nitrogen, oxide of nitrogen (like NO and NO2) have incomplete octet.
While there are few compounds of Br wherein Br has expanded octet. For example, in BrF5, Br has 12 electrons in valence shell. </span>
Answer:
The chemical change in matter is results in a change in its identity and properties.
Explanation:
There are toe type of changes physical change and chemical change.
The chemical change change in matter lead to lost its identity and properties.
Chemical change:
The changes, that occur due to change in the composition of a substance and result in a different compound is known as chemical change.
These changes are irreversible
These changes occur due to chemical reactions
These may not be observed with naked eye
Example:
Combustion of fuel or wood: that oil or wood convert into energy, CO2 and ash in case of wood
Boiling of egg: that change the chemical composition of protein in the egg .
The reaction of Hydrogen and oxygen:
H 2 (g) + O 2 (g) -------------------------------------> 2H 2O (l)