Answer:
transition metals
Explanation:
they're the elements in yellow in the picture
The product of the complete combustion of any fuel (in this case, acetylene) are indeed water and carbon dioxide.
Balancing the combustion reaction,
C2H2 +(5/2) O2 --> 2CO2 + H2O
The number of moles of C2H2 will be,
(12 g) x (1 mole/26 g) = 6/13 mole
Then, the number of moles of O2 is,
(12 g) x (1 mole/32 g) = 3/8 mole
Therefore the limiting reaction is the O2. Getting the amount of CO2 and H2O produced from balancing,
CO2 = (3/8 moles) x (2 moles CO2/ 5/2 mole O2)(44 g/ 1 mole) = 52.8 g
H2O = (3/8 moles) x (1 mole / 5/2 mole O2)(18 g / 1 mole) = 2.7 g
These models are similar because "both the nuclear model and the solar system model have concept of nucleus, electron, positively charged nucleus at center and electrons orbiting around the nucleus".
<u>Explanation:</u>
The points which showcase similarities among both the atomic structure and the composition of the solar system are like the large percentage of the mass centered in the core which is the nucleus or the sun. Attractive forces bring the structure together by application of electromagnetic force or gravitational force.
The existence of the external objects influences the stable state of other surrounding objects as suggested by Pauli theory of exclusion and gravitational disturbance. Overall on the basis of the view only, in both the model their is similarity like atomic model speaks about electrons orbiting the nucleus similar to planets orbiting the sun.
Answer:
Cl2
Explanation:
Cl2 is a covalent molecule because it contains 2 non-metal elements.
It is non-polar because both elements have the same level of electrostatic attraction (remember that electrostatic attraction is the tendency to steel an electron from an element with lower a lower electrostatic force)
In Cl2 since there are only 2 molecules that are the exact same there is no overall dipole (which means that one end of the molecule is slightly positive or negative charge)
If the molecule replaced one Cl or something else then it would be non-polar since one element will be more electrostatic than the other and one region of the molecule will have a slightly positive or negative charge, unless the molecule is symmetrical like CH4.
For CH4 (methane) if you drew this as a lewis structure the Carbon would be surrounded by 4 hydrogen atoms meaning the overall dipole will be cancelled out since the molecule is symmetrical.
You may not understand the last part but just know that:
If there are 2 of the same atoms in the molecule (Cl2) then it is non-polar
If there are 2 non-metals then the bond is covalent
Water is always polar
Answer:
(D) Na₂SO₄•10H₂O (M = 286).
Explanation:
- The depression in freezing point of water by adding a solute is determined using the relation:
<em>ΔTf = i.Kf.m,</em>
Where, ΔTf is the depression in freezing point of water.
i is van't Hoff factor.
Kf is the molal depression constant.
m is the molality of the solute.
- Since, Kf and m is constant for all the mentioned salts. So, the depression in freezing point depends strongly on the van't Hoff factor (i).
- van't Hoff factor is the ratio between the actual concentration of particles produced when the substance is dissolved and the concentration of a substance as calculated from its mass.
(A) CuSO₄•5H₂O:
CuSO₄ is dissociated to Cu⁺² and SO₄²⁻.
So, i = dissociated ions/no. of particles = 2/1 = 2.
B) NiSO₄•6H₂O:
NiSO₄ is dissociated to Ni⁺² and SO₄²⁻.
So, i = dissociated ions/no. of particles = 2/1 = 2.
(C) MgSO₄•7H₂O:
MgSO₄ is dissociated to Mg⁺² and SO₄²⁻.
So, i = dissociated ions/no. of particles = 2/1 = 2.
(D) Na₂SO₄•10H₂O:
Na₂SO₄ is dissociated to 2 Na⁺ and SO₄²⁻.
So, i = dissociated ions/no. of particles = 3/1 = 3.
∴ The salt with the high (i) value is Na₂SO₄•10H₂O.
So, the highest ΔTf resulted by adding Na₂SO₄•10H₂O salt.
