Answer:
true
Explanation:
This is because it helps distribute the particles that are being dissolved.
Answer:
Magnesium nucleus will attract the electrons more toward it and therefore, shrinking the size of the atom. Magnesium atom is smaller than Calcium atom because Calcium has more electron ( 20e− ) which will occupy more energy levels ( n=4 for Calcium versus n=3 for Magnesium)
Answer: The value of the equilibrium constant Kc for this reaction is 3.72
Explanation:
Equilibrium concentration of 
= 
Equilibrium concentration of 
= 
Equilibrium concentration of 
= 
Equilibrium concentration of 
= 
Equilibrium constant is defined as the ratio of concentration of products to the concentration of reactants each raised to the power their stoichiometric ratios. It is expressed as 
For the given chemical reaction:
The expression for is written as:
![K_c=\frac{[NO_2]^3\times [H_2O]^1}{[HNO_3]^2\times [NO]^1}](https://tex.z-dn.net/?f=K_c%3D%5Cfrac%7B%5BNO_2%5D%5E3%5Ctimes%20%5BH_2O%5D%5E1%7D%7B%5BHNO_3%5D%5E2%5Ctimes%20%5BNO%5D%5E1%7D)
Thus the value of the equilibrium constant Kc for this reaction is 3.72
Answer:
The metal cube lattice is made of only one kind of atom.
Explanation:
As we know that metallic crystals are made up of only one kind of element. A metal crystal is actually a huge sea of positive charges embedded in the layers of negative charges (electrons). The whole crystal is made up of same kind of atoms, e.g crystals of gold, crystals of iron.
If we talk about structure of metallic crystal, it can be body centered cubic, simple cubic, hexagonal or close cubic packing.
Now, coming towards the ionic crystals, we know that they are basically the crystals of ionic compounds like sodium chloride or cesium chloride. These crystals are formed due to ionic bonding between two or more than two kinds of elements/atoms. It is not possible for an ionic crystal to be composed of only one kind of atom. As far as structure is concerned, they can have different structure based on bonding between atoms in an ionic compound, e.g NaCl has octahedral geometry.
Therefore, it is very evident that best option is A.
“Water” is the best thermal insulator.
Option: B
<u>Explanation</u>:
“Thermal insulators” are the materials which do not allow heat to transfer. “Water” is the substance which does not transfer heat. Hence, the “water” is the best “thermal insulator”. Water is the bad conductor of thermal heat. Water has “low thermal conductivity” than other substances, so this acts as an insulator as long as it is not traveled from one place to another. Heat is transferred when a “hot object collides” with “the cold objects”. The “thermal conductivity” of “water” is 0.6 W/m K.
