I think the correct answer from the choices listed above is option A. The statement that states a negative impact of chemistry on the society is that hazardous <span>coolants in refrigeration units were replaced. One example of this coolant is the </span><span>production and use of chlorofluorocarbons (CFCs) which replaced by more safer coolants.</span>
Answer:
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<em><u>A</u></em><em><u>N</u></em><em><u>S</u></em><em><u>W</u></em><em><u>E</u></em><em><u>R</u></em></h2>
The second one would be one of the application of an endothermic reaction as because endothermic reaction always have the heat in the process to mix the reactants and form the products as here in a burning wood when the wood is supplied with heat then it change into products as ashes and smoke fumes So here due to the heat is involved to form the products thats the reaction is endothermic reaction.
Hope it helps
Answer:
I think it is 100 if I guess
Answer: Option (b) is the correct answer.
Explanation:
A covalent bond is defined as the bond which occurs due to sharing of electrons between the combining atoms.
Generally, a covalent bond is formed between non-metals.
For example, both nitrogen and oxygen atoms are non-metals and they combine covalently to form 
compound.
As nitrogen has 5 valence electrons and an oxygen atom has 6 valence electrons. So, there occurs unequal sharing of electrons between the two.
Thus, we can conclude that when a covalent bond forms then electrons in valence shells are shared between atoms.
Answer:
The law of conservation of mass states that mass cannot be created or destroyed only transfered. So when a size change takes place the mass is being transfered into something else. During a state change the mass is being transfered into another state of matter. When a substance dissolves into another liquid the mass is still their just into another state.
Explanation:
