Answer:
Explanation:
a) In an exothermic reaction, the energy transferred to the surroundings from forming new bonds is ___more____ than the energy needed to break existing bonds.
b) In an endothermic reaction, the energy transferred to the surroundings from forming new bonds is ___less____ than the energy needed to break existing bonds.
c) The energy change of an exothermic reaction has a _____negative_______ sign.
d) The energy change of an endothermic reaction has a ____positive________ sign.
The energy changes occur during the bonds formation and bonds breaking.
There are two types of reaction endothermic and exothermic reaction.
Endothermic reactions:
The type of reactions in which energy is absorbed are called endothermic reactions.
In this type of reaction energy needed to break the bond are higher than the energy released during bond formation.
For example:
C + H₂O → CO + H₂
ΔH = +131 kj/mol
it can be written as,
C + H₂O + 131 kj/mol → CO + H₂
Exothermic reaction:
The type of reactions in which energy is released are called exothermic reactions.
In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.
For example:
Chemical equation:
C + O₂ → CO₂
ΔH = -393 Kj/mol
it can be written as,
C + O₂ → CO₂ + 393 Kj/mol
O.N. of Na = +1
O.N. of O = -2
Let, O.N. of Tin = x
1*2 + x + -2*2 = 0
2+x-4 = 0
x-2 = 0
x = 2
SO OPTION C IS YOUR ANSWER......
Hi my name is Jaleesa The answer = -1
Answer:
ⁿₐX => ²¹⁸₈₄Po
Explanation:
Let ⁿₐX be the isotope.
Thus, the equation can be written as follow:
²²²₈₆Rn —> ⁴₂α + ⁿₐX
Next, we shall determine the value of 'n' and 'a'. This can be obtained as follow:
222 = 4 + n
Collect like terms
222 – 4 = n
218 = n
Thus,
n = 218
86 = 2 + a
Collect like terms
86 – 2 = a
84 = a
Thus,
a = 84
ⁿₐX => ²¹⁸₈₄Po
²²²₈₆Rn —> ⁴₂α + ⁿₐX
²²²₈₆Rn —> ⁴₂α + ²¹⁸₈₄Po
An educated guess is called estimation
