Answer:
Air temperature is not accurate but it can measure by the air is cold or hot
Hope this will help you
Answer:
A. They are isotopes.
Explanation:
An isotope is an element with the same number of protons but different number of neutrons resulting in a varied mass number/molecular weight.
If you start with the mass of a substance, divide it by its molar mass to find the number of moles of the substance. Then, multiply the number of moles by Avogadro's number, 6.022*10^23, which gives the number of particles per mole of a substance.
Example:
Find the number of atoms in 10 g of CO2.
The mass of a single mole of CO2 is 54 g/mol. You can get this value by adding up the molar masses of the atoms in CO2(12+16+16).
Then divide 10 g by 54 g/mol to get the number of moles of CO2 in 10 g, which is 0.19 mol.
Finally, multiply 0.19 by Avogadro's number to get 1.1*10^23 molecules of CO2.
Explanation:
Let us assume that mass of nickel(II) iodide is 2.90 g, volume is 150.ml, and concentration is 0.70 M.
When is added into the solution then it will not affect the concentration.
Moles of =
=
= 0.00928 mol
Moles of =
=
= 0.01856 mol
Molarity of =
=
= 0.124 M
Thus, we can conclude that final molarity of iodide anion in the solution is 0.124 M.
Answer:
The coefficients in order are 2, 1, 1
Explanation:
Each side of the reaction needs to have the same number of each element due to conservation of matter.
First I looked at what was uneven, notice there are 2 Na on the left side and 4 Na on the left. The easiest way to fix that is to add a 2 on the Na2HPO4:
2(Na2HPO4)--> Na4P2O7 + H2O
Next take count of each element on both sides to see if the 2 balanced everything:
On the left there are 4 Na, 2 H, 2 P, and 8 O
On the right there are 4 Na, 2 H, 2 P, and 8 O
Since both sides match, you are done!