Answer:
b. is always a weak electrolyte.
Explanation:
Such compounds of low solubility dissociates partly and hence cannot be strong electrolytes
Answer:
Formula of EPSOM salt = MgSO4.7H2O
molecular mass of MgSO4.7H2O = atomic mass of Mg + atomic mass of S + 4 × atomic mass of O + 7 { 2 × atomic mass of H + atomic mass of O }
= 24 + 32 + 4× 16 + 7{ 2 × 1 + 16 } g/mol
= (24 + 32 + 64+ 126 ) g/mol
= 246 g/mol
molecular mass of total water = 7 × ( 2× atomic mass of H + atomic mass of O )
= 7 × 18 = 126 g/mol
now ,
% mass of H2O in EPSOM salt = {total molar mass of H2O/molar mass of Epsom salts }× 100
= {126/246 } × 100
= 12600/246
= 51.21 %
Explanation:
i have done it hope it helps
Answer:
-The other substances that give a positive test with AgNO3 are other chlorides present, iodides and bromide.
-It is reasonable to exclude iodides and bromides but it is not reasonable to exclude other chlorides
Explanation:
In the qualitative determination of halogen ions, silver nitrate solution(AgNO3) is usually used. Now, various halide ions will give various colours of precipitate when mixed with with silver nitrate. For example, chlorides(Cl-) normally yield a white precipitate, bromides(Br-) normally yield a cream precipitate while iodides (I-) normally yield a yellow precipitate. Thus, all these ions or some of them may be present in the system.
With that being said, if other chlorides are present, they will also yield a white precipitate just like KCl leading to a false positive test for KCl. However, since other halogen ions yield precipitates of different colours, they don't lead to a false test for KCl. Thus, we can exclude other halides from the tendency to give us a false positive test for KCl but not other chlorides.
A molecular covalent substance (such as co2) has a low melting point because the covalent bonds that hold the molecules together are weak and do not require much energy to break:- False.
What are covalent bonds ?
An electron transfer that leads to the formation of electron pairs between atoms is known as a covalent bond. When atoms share electrons, a stable balance of the repulsive and attractive forces among them is known as covalent bonding. These electron pairs are also known as bonds or shared pairs.
It is a molecular compound, which is a mixture of at least two atoms—the smallest building blocks of matter—joined by a covalent bond. These atoms are joined by a covalent bond, which is formed when electrons are shared.
Learn more about covalent bond here:-
brainly.com/question/19382448
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Answer:
Option-C (27.36% Na, 1.20% H, 14.30% C, and 57.14% O)
Explanation:
<em>Percent Composition</em> is defined as the <u><em>%age by mass of each element present in a compound</em></u>. Therefore, it is a relative amount of each element present in a compound.
Calculating Percent Composition of NaHCO₃:
1: Calculating Molar Masses of all elements present in NaHCO₃:
a) Na = 22.99 g/mol
b) H = 1.01 g/mol
c) C = 12.01 g/mol
d) O₃ = 16.0 × 3 = 48 g/mol
2: Calculating Molecular Mass of NaHCO₃:
Na = 22.99 g/mol
H = 1.01 g/mol
C = 12.01 g/mol
O₃ = 48 g/mol
----------------------------------
Total 84.01 g/mol
3: Divide each element's molar mass by molar mass of NaHCO₃ and multiply it by 100:
For Na:
= 22.99 g.mol⁻¹ ÷ 84.01 g.mol⁻¹ × 100
= 27.36 %
For H:
= 1.01 g.mol⁻¹ ÷ 84.01 g.mol⁻¹ × 100
= 1.20 %
For C:
= 12.01 g.mol⁻¹ ÷ 84.01 g.mol⁻¹ × 100
= 14.29 % ≈ 14.30 %
For O:
= 48.0 g.mol⁻¹ ÷ 84.01 g.mol⁻¹ × 100
= 57.13 % ≈ 57.14 %
