How do you find concentration from absorbance mg and ml?

Which of the following describes metallic character on the periodic table? Question 1 options: A) It increases as you move right

Ilia_Sergeevich [38]

Answer:

D

Explanation:

Metallic character decreases as you move across a period in the periodic table from left to right. This occurs as atoms more readily accept electrons to fill a valence shell than lose them to remove the unfilled shell. Metallic character increases as you move down an element group in the periodic table. This is because electrons become easier to lose as the atomic radius increases, where there is less attraction between the nucleus and the valence electrons because of the increased distance between them.

3 0

3 years ago

A chemist measures the energy change ?H during the following reaction:

Leno4ka [110]

Answer:

(A) endothermic

(A) Yes, absorbed

Explanation:

Let's consider the following thermochemical equation.

2 Fe₂O₃(s) ⇒ 4 FeO(s) + O₂(g) ΔH = 560 kJ

Since ΔH > 0, the reaction is endothermic.

We can establish the following relations:

560 kJ are absorbed when 2 moles of Fe₂O₃ react.
The molar mass of Fe₂O₃ is 160 g/mol.

Suppose 66.6 g of Fe₂O₃ react. The heat absorbed is:

$66.6g.\frac{1mol}{160g} .\frac{560kJ}{2mol} =117kJ$

5 0

3 years ago

In a sample containing 100 atoms of X, 70 were found to be 9X while 30 were 11X isotopes. Determine the average relative atomic

Burka [1]

The average relative atomic mass of a sample containing 100 atoms of X, 70 were found to be 9X while 30 were 11X isotopes is 9.6g.

<h3>What is Atomic mass? </h3>

Atomic mass is defined as the whole mass of an atom.

It is also defined as the sum of atomic number and number of neutrons.

Atomic mass = Atomic number + neutrons

<h3>What is Isotopes?</h3>

Isotopes are the those element which have same atomic number but have different mass number and number of neutrons.

The average relative atomic mass can be calculated as

mass of isotopes/ mass of sample

mass of all isotopes = (70 × 9X) + (30 × 11X)

=(630 + 330) X

= 960X

Average relative atomic mass = 960X/ 100 X

= 9.6 g

Thus, we concluded that the average relative atomic mass of a sample containing 100 atoms of X, 70 were found to be 9X while 30 were 11X isotopes is 9.6g.

learn more about atomic mass:

brainly.com/question/14250653

#SPJ9

5 0

1 year ago

Calculate the energy released when 24.8 g Na2O reacts in the following reaction

WARRIOR [948]

Answer:

hey you wanna get it right try this one: 48.0 kcal

was released... at constant pressure.

Explanation:

5 0

3 years ago

Use this chemical equation to answer the following questions: Cl + O3 ➞ ClO + O2

barxatty [35]

Explanation:

1. Elements are substances made of the same kind of atoms, unlike compounds that are combination for different kinds of atoms. The elements in the reaction therefore are;

Cl and O₃

2. Yes, the equation is balanced. There is the same number of each element on either side of the equation. One (1) CL and three (3) O atoms.

3. Ozone is reduced. Other the other hand, Cl is oxidized. Remember a reduction reaction may involve the loss of one or more oxygen atoms or the acceptance of electrons. This occurs for O₃ which is reduced to O₂.

4. The equation complies with the conservation of matter as in the first law of thermodynamics. The number of atoms for each element on the other side of the equation remains the same. This means no matter(which also translated to energy) has been created or destroyed in the process.

4 0

3 years ago