Answer:
C.
Explanation:
The hand was touching the pan, which was hot, so the human reacted to it by putting the hand away from the pan.
Answer:
2Zn + 2HCl = H2 + 2ZnCl
Explanation:
Zn is a metal, when metals have reaction with strong acid it will produce H2 gas and the metal's salt which is ZnCl.
Later on you just make the equation in balance.
Force /Area = Pressure
Force = Pressure * Area
Force = 1065 * 17 = 18105 N
weight = 18105 N
I hope this helps!
Answer:
1.48 x 10^47 mol of Na
Explanation:
8.90 x 10^24 atoms of Na (1 mol of Na/6.022 x 10^23 atoms of Na)=
1.48 x 10^47 mol of Na
We have to discuss here whether mole should be considered as a base unit in SI system or not.
The answer is- mole is considered as base unit in SI system.
There are seven base units in the SI system. They are- kilogram (kg) for mass, second (s) for time, kelvin (K) for temperature, ampere (A) for electric current, mole (mol) for the amount of substance, candela (cd) for luminous intensity and meter (m) is for distance.
Mole is defined as the amount of substance that contains as many elementary entities as there are atoms in 0.012 kilogram of carbon-12. One mole contains exactly 6.022 X 10²³ elementary entities.
This number 6.022 X 10²³ is the fixed numerical value which is called Avogadro number which is universally accepted number. Hence mole is also base unit in the SI system.
