You need to have 8 electrons to fill an atom and to fill bond the pairs need to equal 8
Answer: ice is less dense than liquid water. If ice was more dense, Earth would freeze.
Explanation: There are many reasons why life on Earth depends on the characteristics of water. One could discuss hydrogen bonds and its role as a solvent, but the unusual property of water is is the change in density with change in temperature. Water is densest at 4 degC, which is why ice floats - it is less dense than cold water (it melts quickly in warm water, so density isn’t impotant at higher temperatures). Most liquids are less dense than the solid, frozen form. If this was the case with water, any ice that formed would sink, and sease would freeze from the bottom up. Furthermore, the lowest layers would be insulated and would not all melt in summer. Thus over time, the seas would become a thin layer of liquid water at best, over solid ice. Life could not develop without liquid seas. In addition, ice is reflective, reducing the amount of sunlight absorbed, further reducing temperatures. Without ocean circulation, polar areas would be even colder, and there would be no rain.
Answer : The correct option is, (D) double replacement reaction
Explanation :
Synthesis reaction : A chemical reaction where multiple substances or reactants combine to form a single product.
It is represented as,
Decomposition reaction : A chemical reaction in which larger reactant decomposes to give two or more than two products.
It is represented as,
Single replacement reaction : A chemical reaction in which the more reactive element replace the less reactive element.
It is represented as,
In this reaction, A is more reactive element and B is less reactive element.
Double replacement reaction : It is a type of chemical reaction where a positive cation and a negative anion of two reactants exchange places to form two new products.
It is represented as,
(X and A are the cations, Y and B are the anions)
The given reaction is:
This reaction is a double displacement reaction.
Answer:
The answer to your question is the second one
Explanation:
AC + B → AB + C
This is not the right answer, the reaction shown here is a single replacement reaction in which one element replaces another element that is part of a compound.
A + B + C → ABC
This is the right answer because in synthesis reactions two or more reactants bound to form only one product.
ABC → A + B + C
This answer is incorrect because this is an example of a decomposition reaction in which one reactant forms two or more products.
AB + CD → AC + BD
This is an example of double replacement reaction in which the cations and anions of the reactants are interchanged.
