Answer:
All of the above.
Explanation:
In positive deviation from Raoult's Law occur when the vapour pressure of components is greater than what is expected value in Raoult's law.
When a solution is non ideal then it shows positive or negative deviation.
Let two solutions A and B to form non- ideal solutions.let the vapour pressure of component A is 
and vapour pressure of component B is 
.
= Vapour pressure of component A in pure form
= Vapour pressure of component B in pure form
=Mole fraction of component A
=Mole fraction of component B
The interaction between A- B is less than the interaction A- A and B-B interaction.Therefore, the escaping tendency of liquid molecules in mixture is greater than the escaping tendency in pure form.Hence, the vapour pressure of a mixture is greater than the initial value of vapour pressure.
,
Therefore, 
Therefore, the enthalpy of mixing is greater than zero and change in volume is greater than zero.
Hence, option a,b,c and d are true.
Answer: 125 g
Explanation:
To calculate the moles :
The balanced reaction is:
According to stoichiometry :
1 mole of 
require = 3 moles of 
Thus 1.30 moles of will require=
of
Mass of 
Thus 125 g of will be needed to burn 36.1 g of
Answer:
2 chlorine atoms.
Explanation:
H₂ + Cl₂ → 2HCl
The Law of Conservation of Mass states that matter can neither be created nor destroyed in a chemical reaction.
If 2 molecules of Hydrogen and 2 molecules of Chlorine is present in the reactants, the same no. of atoms should also be present in the product.
∴ the no. of chlorine atoms in the product is 2.
Answer:
Dmitri Mendeleev
Explanation:
Dmitri Mendeleev a Russian Chemist arranged elements on the periodic table according to their atomic mass. He used this arrangement to predict some of the properties of the missing element.
- Dmitri Mendeleev around 1869 described the periodic table.
- The table was based on the periodic law which states that "chemical properties of elements are a periodic function of their atomic weights".
- In the Mendeleev table, elements are arranged by atomic weights with recurring properties in a periodic manner.
Answer:- 
and 
Explanations:- In the first equation, the oxidation number of O is decreasing from 0 to -2 where as the oxidation number of H is increasing from 0 to +1. As the oxidation number is increasing for one element(H) and decreasing for other element(O), it is an oxidation-reduction reaction.
Second reaction is a double displacement reaction so there is no change to the oxidation numbers of the elements and hence it is not oxidation-reduction reaction.
In third reaction, the oxidation number of Al is increasing from 0 to +3 and the oxidation number of H is decreasing from +1 to 0. Here again there is an increase and decrease to the oxidation numbers of two elements, it is oxidation-reduction reaction.
fourth and fifth reactions are again double displacement reactions and so there is no change to oxidation numbers for any of the elements and they are not the oxidation-reduction reactions.
So, the only correct equations are and .
