I believe B) in both chemical changes and physical changes since in chemical changes, nothing is created or destroyed. In physical changes same thing but with matter.
Answer is no
The chemical reaction between iron and oxygen in the presence of moisture or water produces a new substance, which is the rust (iron oxide). In this case, it shows a chemical property.
374u
187u
C₁₄H₂₂N₄O₈
Explanation:
To find the molecular weight of the compound C₁₄H₂₂N₄O₈ we simply sum that atomic masses of the given elements in the compound.
The empirical weight is determined by using the simplest ratio of the elements involved in the compound;
Molecular weight of C₁₄H₂₂N₄O₈;
atomic mass of C = 12g/mol
H = 1g/mol
N = 14g/mol
O = 16g/mol
Molecular weight = 14(12) + 22(1) + 4(14) + 8(16)
= 168 + 22 + 56 + 128
= 374u
Empirical weight:
Empirical formula:
C₁₄ H₂₂ N₄ O₈
14 : 22 : 4 : 8
divide by 2:
7 : 11 : 2 : 4
empirical formula C₇H₁₁N₂O₄
empirical weight =
=
= 187u
The molecular formula is the actual combination of atoms in a compound. so the molecular formula of the compound is C₁₄H₂₂N₄O₈
learn more:
Molecular mass brainly.com/question/5546238
#learnwithBrainly
<u>Answer:</u> The molar mass of molecule X is 162.5 g/mol
<u>Explanation:</u>
We are given:
0.9 % of NaCl
This means that 0.9 grams of NaCl is present in 100 grams of solution
5 % of molecule X
This means that 5 grams of molecule X is present in 100 grams of solution
To calculate the concentration of solute, we use the equation for osmotic pressure, which is:
![\pi=iMRT](https://tex.z-dn.net/?f=%5Cpi%3DiMRT)
Or,
![\pi=i\times \frac{\text{Mass of solute}}{\text{Molar mass of solute}\times \text{Volume of solution (in L)}}\times RT](https://tex.z-dn.net/?f=%5Cpi%3Di%5Ctimes%20%5Cfrac%7B%5Ctext%7BMass%20of%20solute%7D%7D%7B%5Ctext%7BMolar%20mass%20of%20solute%7D%5Ctimes%20%5Ctext%7BVolume%20of%20solution%20%28in%20L%29%7D%7D%5Ctimes%20RT)
where,
i = Van't hoff factor
R = Gas constant = ![0.0821\text{ L atm }mol^{-1}K^{-1}](https://tex.z-dn.net/?f=0.0821%5Ctext%7B%20L%20atm%20%7Dmol%5E%7B-1%7DK%5E%7B-1%7D)
T = temperature of the solution
According to the question:
Osmotic pressure of both the solutions are same.
So, the equation becomes:
![i_{NaCl}\times \frac{m_{NaCl}}{M_{NaCl}\times V}\times RT=i_X\times \frac{m_X}{M_X\times V}\times RT](https://tex.z-dn.net/?f=i_%7BNaCl%7D%5Ctimes%20%5Cfrac%7Bm_%7BNaCl%7D%7D%7BM_%7BNaCl%7D%5Ctimes%20V%7D%5Ctimes%20RT%3Di_X%5Ctimes%20%5Cfrac%7Bm_X%7D%7BM_X%5Ctimes%20V%7D%5Ctimes%20RT)
where,
![i_{NaCl}=2\\m_{NaCl}=0.9g\\M_{NaCl}=58.5g/mol\\i_X=1\text{ (for non-electrolytes)}\\m_X=5g\\M_X=?g/mol](https://tex.z-dn.net/?f=i_%7BNaCl%7D%3D2%5C%5Cm_%7BNaCl%7D%3D0.9g%5C%5CM_%7BNaCl%7D%3D58.5g%2Fmol%5C%5Ci_X%3D1%5Ctext%7B%20%28for%20non-electrolytes%29%7D%5C%5Cm_X%3D5g%5C%5CM_X%3D%3Fg%2Fmol)
Putting values in above equation, we get:
![2\times \frac{0.9}{58.5\times V}\times RT=1\times \frac{5}{M_X\times V}\times RT\\\\M_X=\frac{1\times 5\times 58.5}{0.9\times 2}=162.5g/mol](https://tex.z-dn.net/?f=2%5Ctimes%20%5Cfrac%7B0.9%7D%7B58.5%5Ctimes%20V%7D%5Ctimes%20RT%3D1%5Ctimes%20%5Cfrac%7B5%7D%7BM_X%5Ctimes%20V%7D%5Ctimes%20RT%5C%5C%5C%5CM_X%3D%5Cfrac%7B1%5Ctimes%205%5Ctimes%2058.5%7D%7B0.9%5Ctimes%202%7D%3D162.5g%2Fmol)
Hence, the molar mass of molecule X is 162.5 g/mol