How did Mendeleev come up with the first periodic table of the elements? (1 point)A He determined the mass of atoms of each element.
B He estimated the number of electrons in atoms of each element.
C He arranged the elements by different properties to find a pattern.
D He organized the elements by their atomic number.​

Answer: Yes

Explanation:

Density of a liquid depend on its volume. This is because Density is mass of liquid divided by volume.

Density is inversely proportional to volume.

As density increases, volume decreases and vice versa. The density for water is 1g/ milliliter but it changes with changes in temperature or there are impurities dissolved in it. Ice is less dense that liquid water and it's the major reason it's float because it's volume is inversely proportional to it's density.

Explanation:

Law of conservation of mass states that mass can neither be created nor it can be destroyed but it can be transformed into one form to another.

Similarly, law of conservation of energy states that energy can neither be created nor it can be destroyed as it can only be transformed from one form to another.

In modern view of matter and energy, is the law of mass conservation still relevant to chemical reactions as follows.

For example,

Atomic mass of Na = 23

Atomic mass of Cl = 35

Hence, mass of total number of reactants is calculated as follows.

             [(2 \times 23) + (35 \times 2)] g/mol = 116 g/mol

Mass of total number of products is calculated as follows.

             [2 \times (23 + 35)] = 116 g/mol

Thus, it is proved that in our modern view of matter and energy, is the law of mass conservation still relevant to chemical reactions.

Answer:

a) D = 33.44 Lbmol/h

⇒ B = 62.56 Lbmol/h

b) D = 16.848 Kmol/h

⇒ B = 28.152 Kmol/h

Explanation:

global balance:

• F = D + B........................(1)

∴ F = 100 Lbmol/h

balance per component:

A: 0.4*F = 0.9*D + 0.1*B = 0.4*100 = 40 Lbmol/h..............(2)

B: 0.6*F = 0.1*D + 0.9*B = 0.6*100 = 60 Lbmol/h..............(3)

from (2):

⇒ 0.9*D = 40 - 0.1*B

⇒ D = ( 40 - 0.1*B ) / 0.9............(4)

(4) in (3):

⇒ 0.1*((40-0.1*B)/0.9) + 0.9*B = 60

⇒ B = 62.56 Lbmol/h............(5)

(5) in (1):

⇒ D = 100 - B

⇒ D = 37.44 Lbmol/h

∴ Lbmol = 0.45 Kmol

⇒ B = 62.56 Lbmol/h * ( 0.45 Kmol/ Lbmol ) = 28.152 Kmol/h

⇒ D = 37.44 Lbmol/h * ( 0.45 Kmol/h ) = 16.848 Kmol/h

Answer:

0.051

Explanation:

Let's consider the following reaction.

2 SO₂(g) + O₂(g) ⇄ 2 SO₃(g)

We can compute the pressures using an ICE chart.

         2 SO₂(g) + O₂(g) ⇄ 2 SO₃(g)

I             3.3         0.79           0

C           -2x            -x           +2x

E         3.3-2x      0.79-x         2x

The partial pressure of sulfur trioxide gas is 0.47 atm. Then,

2x = 0.47

x = 0.24

The pressures at equilibrium are:

pSO₂ = 3.3-2x = 3.3-2(0.24) = 2.82 atm

pO₂ = 0.79-x = 0.79-0.24 = 0.55 atm

pSO₃ = 0.47 atm

The pressure equilibrium constant (Kp) is:

Kp = pSO₃² / pSO₂² × pO₂

Kp = 0.47² / 2.82² × 0.55

Kp = 0.051

Answer:

To obtain the pH of 8.0, the concentration of NaOCl needs to be 0.9 M in the 0.3 M HOCl solution

Explanation:

This problem can be solved by Henderson-Hasselbalch equation, which gives relation between the concentration of acid, its salt, pKa and the pH of the solution. This equation is given as,

By placing the known variables in the above equation we get,

The above calculations show that the required concentration of NaOCl is 0.9 M.