Answer:
the land is heated through radiant energy,
Explanation:
Answer:
The result is 3.859 in which we use four significant figures.
Explanation:
We start by solving the mathematical operation :

The result for the operation is 3.859438 but the numbers in the operation are given with four significant figures and that is why we are going to use four significant figures to express the result
To express 3.859438 with four significant figures we use the first four digits that appear from left to right starting by the first digit that is different to zero
In this case : 3.859 will be the result with four significant figures.
We also use a rule that says : To decide if the last significant figure remains the same we look for the value of the digit at its right.
If that number is greater than or equal to 5 ⇒ we sum one to the last significant figure
For example 3.859738 = 3.860 with four significant figures because the ''7'' is greater that 5
If that number is less than 5 ⇒ the last significant figure remains the same
In our case : 3.859438 = 3.859 because ''4'' is less than ''5''
Answer:
2RbNO₃ + BeF₂ → Be(NO₃)₂ + 2RbF, because Be keeps a 2+ charge throughout the reaction
Explanation:
2RbNO₃ + BeF₂ → Be(NO₃)₂ + 2RbF, because Be keeps a 2+ charge throughout the reaction
Rb is a +1 cation, NO3 is a -1 anion, Be is a +2 cation and F is a -1 anion.
In writing an ionic compound the charge of the cation becomes the subscript of the anion and the charge of the anion becomes the subscript of the cation.
So the ionic compound formed between Be2+ and F- is BeF2. The ionic compound formed between Be2+ and NO3- is Be(NO₃)₂.
As there are two NO₃ on the product side it is balanced by writing a 2 coefficient before RbNO₃ on the reactant side.
And as there are two F on the reactant side it is balanced by writing a 2 coefficient before RbF on the product side.
Answer:
An acid increases the hydrogen ion concentration in a solution, while a base decreases the hydrogen ion concentration. Solutions with a pH of less than seven are acidic, while those with a pH greater than seven are basic (alkaline).
Explanation: