Answer : The expected coordination number of NaBr is, 6.
Explanation :
Cation-anion radius ratio : It is defined as the ratio of the ionic radius of the cation to the ionic radius of the anion in a cation-anion compound.
This is represented by,
When the radius ratio is greater than 0.155, then the compound will be stable.
Now we have to determine the radius ration for NaBr.
Given:
Radius of cation, 
= 102 pm
Radius of cation, 
= 196 pm
As per question, the radius of cation-anion ratio is between 0.414-0.732. So, the coordination number of NaBr will be, 6.
The relation between radius ratio and coordination number are shown below.
Therefore, the expected coordination number of NaBr is, 6.
Mass of methanol (CH3OH) = 1.922 g
Change in Temperature (t) = 4.20°C
Heat capacity of the bomb plus water = 10.4 KJ/oC
The heat absorbed by the bomb and water is equal to the product of the heat capacity and the temperature change.
Let’s assume that no heat is lost to the surroundings. First, let’s calculate the heat changes in the calorimeter. This is calculated using the formula shown below:
qcal = Ccalt
Where, qcal = heat of reaction
Ccal = heat capacity of calorimeter
t = change in temperature of the sample
Now, let’s calculate qcal:
qcal = (10.4 kJ/°C)(4.20°C)
= 43.68 kJ
Always qsys = qcal + qrxn = 0,
qrxn = -43.68 kJ
The heat change of the reaction is - 43.68 kJ which is the heat released by the combustion of 1.922 g of CH3OH. Therefore, the conversion factor is:
Answer:
88.8 minutes
Explanation:
Graham's law of diffusion relates rate of difusion by the following formula
Rate1 / rate 2 = √( Mass of argon / Mass of Neon)
Where rate = volume divided by time
Rate 1 = 10 ml / t1
Rate 2 = 10 ml / t2
Rate 1/ rate 2 = 10 ml / t1 ÷ 10 ml/ t2 = t2/ t1
t2/t1 = √(Mass of argon / mass of Neon) = √( 39.984/20.179)
125 / t1 = 1.4026
t1 = 125 / 1.4026 = 88.8 minutes
Answer:
Explanation:
Density of gold is 19.3 g / cm³
Density of copper is 8.96 g / cm³
Density of bronze is 8.7 g / cm³
Hence when the gold and copper or bronze are mixed , the density of gold will be reduced due to less density of copper and bronze in comparison to that of gold.
We consider that the 50% given in this item is by volume. Molarity is the unit of concentration that takes into account the number of moles of the solute and the number of moles of the substance.
number of moles of NaOH = (0.1 moles / L)(0.4 L)
n = 0.04 moles of NaOH
If we are to take the basis of 1 mL of 50% NaOH solution,
(1 mL solution)(1.525 g/mL)(0.50) = 0.7625 g
The number of moles is,
0.7625 g NaOH x (1 mol / 40 g) = 0.01906 moles of NaOH
volume of solution required = (0.04 moles of NaOH)(1 mL solution / 0.01906 moles of NaOH)
volume of solution required = 2.09 mL
Answer: 2.09 mL
