Answer:
Endothermic reaction chemical equation
Reactnt A + Reactant B + Heat (energy) ⇒ Products
Exothermic reaction chemical equation
Reactnt A + Reactant B ⇒ Products + Heat (energy)
Explanation:
Endothermic Reaction
An endothermic reaction is a reaction that reaction that requires heat before it would take place resulting in the absorption of heat from the surrounding that can be sensed by the coolness of the reacting system
An example of an endothermic reaction is a chemical cold pack that becomes cold when the chemical and water inside it reacts
Exothermic Reaction
An exothermic reaction is one that rekeases energy to the surroundings when it takes place. This is as a result of the fact that the combined heat energy of the reactants is more than the chemical heat energy of the products. An example of an exothermic reaction is a burning candle
Friction .......................................................................................
The molecule have TETRAHEDRAL HYBRID ORBITAL.
SP3 hybridization involves the mixing of one orbital of S sub level and three orbitals of P sub level of the valence shell. All the orbitals possess equivalent energies and shapes. The SP3 orbital has 25% S character and 75% P character. S and P refers to the s and p sub shells.<span />
Answer:
A
Explanation:
add 22 with the answers like A, 33+22=55
Isotopes are atoms of the same element that differ in the number of neutrons.
Remember that all the atoms of an element have the same number of protons. So the only difference between isotopes of an element is the number of neutrons.
86 Sr means that the mass number of this isotope is 86. Also, remember that the mass number is the number of protons plus the number of neutrons.
87 Sr means that the mass number of this isotope is 87.
So, 86 Sr and 87 Sr differ 1 neutron.
Answer: 1 neutron
