Answer:
0.480 grams
Explanation:
Li₃N(s) + 3D₂O (L) --------------------------> ND₃(g) + 3LiOD (aq)
1 : 3 : 1 : 3
Number of moles (n) = Mass in gram/ Molar Mass
Mass of ND₃ = 160 mg
= 0.16 g
Molar mass of ND₃= [14 + (3 x 2.014 )]
= 14 + 6.042
= 20.042 g/mol
Number of moles of ND₃ = 0.16/20.042
= 0.007983 moles
From the reaction equation, the mole ratio between Heavy water (D₂O ) and ND₃ is 3: 1.
This implies that the number of moles of Heavy water (D₂O ) required
= 3 x 0.007983 moles
= 0.023949 moles
Molar mass of Heavy water (D₂O )= [(2.014 x 2) + 16]
= 20.028 g/mol
Mass in grams of Heavy water (D₂O )= Number of moles x Molar mass
= 0.023949 x 20.028
= 0.4797 grams
≈ 0.480 grams
Answer:
The piece of wood will sink
Explanation:
If an object has a density higher than water, it will sink, and the piece of wood is more dense than water when measured.
Answer:
The correct answer is - Statement I is true, Statement-II is false.
Explanation:
Answer:
B) All carbon atoms have 6 neutrons.
Explanation:
The false statement from the given choices is that all carbon atoms have 6 neutrons.
There is a phenomenon called isotopy in chemistry.
Isotopy is the existence of two or more atoms of the same element having the same atomic number but different mass numbers due to the differences in the number of neutrons in their various nuclei.
- These atoms of elements are called isotopes.
- Carbon atoms generally have proton number of 6 which is the same as the atomic number.
- As with all atoms, the mass number or atomic mass equals the number of protons and neutrons.
For the isotopes of carbon, their number of neutrons differs.
For example:
<em>¹²₆C ¹³₆C ¹⁴₆C</em>
The number of neutrons differs in the above isotopes.
Number of neutrons = mass number - atomic number;
¹²₆C , number of neutrons = 12 - 6 = 6
¹³₆C, number of neutrons = 13 - 6 = 7
¹⁴₆C, number of neutrons = 14 - 6 = 8
Therefore, based on the concept of isotopy, all carbon atoms do not have 6 neutrons.
Explanation:
With all the scaling up and design improvements, the flight range of the R-7 increased to an intercontinental distance from 330 kilometers for the V-2. The R-7 ended up looking oversized even next to its American contemporaries -- the Atlas and Titan ballistic missiles.
