You get 42 when you multiply 6 & 7.
Answer:
7.53×10²³ molecules
Explanation:
Given data:
Number of moles of carbonic acid = 1.25 mol
Number of molecules of CO₂ produced = ?
Solution:
Chemical equation:
H₂CO₃ → CO₂ + H₂O
Now we will compare the number of moles of carbonic acid with CO₂ from balanced chemical equation.
H₂CO₃ : CO₂
1 : 1
1.25 : 1.25
Number of molecules can be determine by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
Number of molecules:
1 mole = 6.022 × 10²³ molecules
1.25 mol × 6.022 × 10²³ molecules / 1 mol
7.53×10²³ molecules
Answer: The staircase is 14.28 m high.
Explanation:
Given : Mass = 0.1 kg
Potential energy = 14 J
Potential energy is the energy occupied by the position of a substance. Therefore, formula for potential energy is as follows.
P.E = mgh
where,
m = mass
g = gravitational energy = 
h = height of object
Substitute the values into above formula as follows.
Thus, we can conclude that the staircase is 14.28 m high.
Answer;
C) 228/90Th
Explanation;
-The above nuclear equation shows a beta radiation. The nuclide X undergoes beta radiation to form 228/89 Ac.
- When an unstable nuclide undergoes beta radiation the mass number remains the same while the atomic number is increased by one.
-Therefore, we can get the mass number and the atomic number of nuclide X, The mass number would be the same as 228 (its not affected by beta radiation) and the atomic number would be 89 (88+1).
