Question

Найти молекулярную массу и массовую долю. Na3PO4 CuS Al (No2)3 CaF2 Ba(NO2)2

Answer 1

M(Na3PO4)=23*3+31+16*4=164 w(Na)=69/164=0.42(42%) w(P)=31/164=0.19(19%) w(O)=64/164=0.39(39%)

CuS=64+32=96 w(Cu)=64/96=67% w(S)=32/96=33%

Al(NO2)3=27+14*3+16*6=165 w(Al)=27/165=16% W(N)= 14*3/165=25% w(O)=16*6/165=59%

CaF2=40+19*2=78 w(Ca)=40/78=51% w(F)=38/78=49%

Ba(NO2)2=137+28+64=229 w(Ba)=137/229=60% w(N)=28/229=12% w(O)=64/229=28%

Answer 2

Molecular Mass and Mass Fraction of Compounds

To find the molecular mass and mass fraction of the given compounds, let's calculate them one by one:

1. Na3PO4: - Molecular mass: The molecular formula of sodium phosphate (Na3PO4) indicates that it contains 3 sodium atoms (Na), 1 phosphorus atom (P), and 4 oxygen atoms (O). The atomic masses of sodium, phosphorus, and oxygen are approximately 22.99 g/mol, 30.97 g/mol, and 16.00 g/mol, respectively. Therefore, the molecular mass of Na3PO4 can be calculated as follows: ``` Molecular mass of Na3PO4 = (3 * atomic mass of Na) + atomic mass of P + (4 * atomic mass of O) = (3 * 22.99 g/mol) + 30.97 g/mol + (4 * 16.00 g/mol) = 69.00 g/mol + 30.97 g/mol + 64.00 g/mol = 163.97 g/mol ``` - Mass fraction: To calculate the mass fraction of each element in Na3PO4, we need to divide the mass of each element by the total molecular mass of Na3PO4. The mass fraction can be expressed as a percentage. - Mass fraction of sodium (Na): ``` Mass fraction of Na = (3 * atomic mass of Na) / molecular mass of Na3PO4 * 100% = (3 * 22.99 g/mol) / 163.97 g/mol * 100% = 34.48% ``` - Mass fraction of phosphorus (P): ``` Mass fraction of P = atomic mass of P / molecular mass of Na3PO4 * 100% = 30.97 g/mol / 163.97 g/mol * 100% = 18.91% ``` - Mass fraction of oxygen (O): ``` Mass fraction of O = (4 * atomic mass of O) / molecular mass of Na3PO4 * 100% = (4 * 16.00 g/mol) / 163.97 g/mol * 100% = 46.61% ```

2. CuS: - Molecular mass: The molecular formula of copper sulfide (CuS) indicates that it contains 1 copper atom (Cu) and 1 sulfur atom (S). The atomic masses of copper and sulfur are approximately 63.55 g/mol and 32.07 g/mol, respectively. Therefore, the molecular mass of CuS can be calculated as follows: ``` Molecular mass of CuS = atomic mass of Cu + atomic mass of S = 63.55 g/mol + 32.07 g/mol = 95.62 g/mol ``` - Mass fraction: To calculate the mass fraction of each element in CuS, we need to divide the mass of each element by the total molecular mass of CuS. The mass fraction can be expressed as a percentage. - Mass fraction of copper (Cu): ``` Mass fraction of Cu = atomic mass of Cu / molecular mass of CuS * 100% = 63.55 g/mol / 95.62 g/mol * 100% = 66.50% ``` - Mass fraction of sulfur (S): ``` Mass fraction of S = atomic mass of S / molecular mass of CuS * 100% = 32.07 g/mol / 95.62 g/mol * 100% = 33.50% ```

3. Al(NO2)3: - Molecular mass: The molecular formula of aluminum nitrite (Al(NO2)3) indicates that it contains 1 aluminum atom (Al), 3 nitrogen atoms (N), and 6 oxygen atoms (O). The atomic masses of aluminum, nitrogen, and oxygen are approximately 26.98 g/mol, 14.01 g/mol, and 16.00 g/mol, respectively. Therefore, the molecular mass of Al(NO2)3 can be calculated as follows: ``` Molecular mass of Al(NO2)3 = atomic mass of Al + (3 * atomic mass of N) + (6 * atomic mass of O) = 26.98 g/mol + (3 * 14.01 g/mol) + (6 * 16.00 g/mol) = 26.98 g/mol + 42.03 g/mol + 96.00 g/mol = 164.01 g/mol ``` - Mass fraction: To calculate the mass fraction of each element in Al(NO2)3, we need to divide the mass of each element by the total molecular mass of Al(NO2)3. The mass fraction can be expressed as a percentage. - Mass fraction of aluminum (Al): ``` Mass fraction of Al = atomic mass of Al / molecular mass of Al(NO2)3 * 100% = 26.98 g/mol / 164.01 g/mol * 100% = 16.46% ``` - Mass fraction of nitrogen (N): ``` Mass fraction of N = (3 * atomic mass of N) / molecular mass of Al(NO2)3 * 100% = (3 * 14.01 g/mol) / 164.01 g/mol * 100% = 12.84% ``` - Mass fraction of oxygen (O): ``` Mass fraction of O = (6 * atomic mass of O) / molecular mass of Al(NO2)3 * 100% = (6 * 16.00 g/mol) / 164.01 g/mol * 100% = 70.70% ```

4. CaF2: - Molecular mass: The molecular formula of calcium fluoride (CaF2) indicates that it contains 1 calcium atom (Ca) and 2 fluorine atoms (F). The atomic masses of calcium and fluorine are approximately 40.08 g/mol and 18.99 g/mol, respectively. Therefore, the molecular mass of CaF2 can be calculated as follows: ``` Molecular mass of CaF2 = atomic mass of Ca + (2 * atomic mass of F) = 40.08 g/mol + (2 * 18.99 g/mol) = 40.08 g/mol + 37.98 g/mol = 78.06 g/mol ``` - Mass fraction: To calculate the mass fraction of each element in CaF2, we need to divide the mass of each element by the total molecular mass of CaF2. The mass fraction can be expressed as a percentage. - Mass fraction of calcium (Ca): ``` Mass fraction of Ca = atomic mass of Ca / molecular mass of CaF2 * 100% = 40.08 g/mol / 78.06 g/mol * 100% = 51.34% ``` - Mass fraction of fluorine (F): ``` Mass fraction of F = (2 * atomic mass of F) / molecular mass of CaF2 * 100% = (2 * 18.99 g/mol) / 78.06 g/mol * 100% = 48.66% ```

5. Ba(NO2)2: - Molecular mass: The molecular formula of barium nitrite (Ba(NO2)2) indicates that it contains 1 barium atom (Ba), 2 nitrogen atoms (N), and 4 oxygen atoms (O). The atomic masses of barium, nitrogen, and oxygen are approximately 137.33 g/mol, 14.01 g/mol, and 16.00 g/mol, respectively. Therefore, the molecular mass of Ba(NO2)2 can be calculated as follows: ``` Molecular mass of Ba(NO2)2 = atomic mass of Ba + (2 * atomic mass of N) + (4 * atomic mass of O) = 137.33 g/mol + (2 * 14.01 g/mol) + (4 * 16.00 g/mol) = 137.33 g/mol + 28.02 g/mol + 64.00 g/mol = 229.35 g/mol ``` - Mass fraction: To calculate the mass fraction of each element in Ba(NO2)2, we need to divide the mass of each element by the total molecular mass of Ba(NO2)2. The mass fraction can be expressed as a percentage. - Mass fraction of barium (Ba): ``` Mass fraction of Ba = atomic mass of Ba / molecular mass of Ba(NO2)2 * 100% = 137.33 g/mol / 229.35 g/mol * 100% = 59.89% ``` - Mass fraction of nitrogen (N): ``` Mass fraction of N = (2 * atomic mass of N) / molecular mass of Ba(NO2)2 * 100% = (2 * 14.01 g/mol) / 229.35 g/mol * 100% = 12.20% ``` - Mass fraction of oxygen (O): ``` Mass fraction of O = (4 * atomic mass of O) / molecular mass of Ba(NO2)2 * 100% = (4 * 16.00 g/mol) / 229.35 g/mol * 100% = 28.91% ```

Please note that the calculations provided above are based on the atomic masses of the elements and the