All categories

3 years ago

#1: How are the elements arranged in the modern periodic table?

Chemistry

2 answers:

Alekssandra [29.7K]3 years ago

4 0

1- The correct answer is C :

the elements arranged in the modern periodic table by increasing atomic number.

The explanation:

-The elements in the periodic table are arranged to increase the atomic number. All of these elements display several other trends and we can use the periodic law and table formation to predict their chemical, physical, and atomic properties.

2- The correct answer is C:

strontium, magnesium, calcium, beryllium are the elements which have similar properties.

The explanation:

-strontium, magnesium, calcium, beryllium, these belong to the alkaline earth metal group.

Because the outer electron structure in all of these elements is similar, they all have somewhat similar chemical and physical properties .

3- The correct answer is A :

Potassium

The explanation:

-The elements potassium and sodium have similar chemical properties because they have the same number of valence electrons and form +1 ions.

4- The correct answer is D

The explanation:

Mendeleev didn't include helium, neon, and argon in his periodic table because these elements had not yet been discovered.

5- The correct answer is B:

The periodic law describes trends seen across periods within the periodic table.

The explanation:

When the chemical elements are arranged, there is a pattern called the “periodic law” in their properties, in which elements in the same column (group) have similar properties

Tju [1.3M]3 years ago

3 0

1. The elements are arranged in the modern periodic table by increasing atomic number. The correct option is option "C".

2. "Strontium, magnesium, calcium, beryllium" are the elements among the choices given in the question are the elements having similar properties. The correct option is option "C".

3. "Potassium" is the element among the choices given in the question that has properties most similar to sodium. The correct option is option "A".

4. Mendeleev didn't include helium, neon, and argon in his periodic table because these elements had not yet been discovered. The correct option is option "D".

5. The periodic law describes trends seen across periods within the periodic table. The correct option is option "B".

You might be interested in

Apply solubility rules of inorganic slats to predict the occurance of precipitation reactions?

kakasveta [241]

Explanation:

An ionic solution is when a compound's ions in an aqueous solution have dissociated. As you combine two aqueous solutions, a reaction occurs. This is when you find out whether or not a precipitate is going to form. A precipitate occurs when the ion reaction component in water is insoluble.The formation of a precipitate is an indication that a chemical change has occurred. for example if we mix clear solutions of silver nitrate and sodium chloride, sodium nitrate is formed which is a precipitate.

5 0

3 years ago

Chlorine has two naturally occurring isotopes, 35C1 Gsotopic mass 34.9689 amu) and 370 (isotopic mass 36.9659 amu). If chlorine

Lilit [14]

Answer: The percentage abundance of $_{17}^{35}\textrm{Cl}$ and $_{17}^{37}\textrm{Cl}$ isotopes are 75.77% and 24.23% respectively.

Explanation:

Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.

Formula used to calculate average atomic mass follows:

$\text{Average atomic mass }=\sum_{i=1}^n\text{(Atomic mass of an isotopes)}_i\times \text{(Fractional abundance})_i$ .....(1)

Let the fractional abundance of $_{17}^{35}\textrm{Cl}$ isotope be 'x'. So, fractional abundance of $_{17}^{37}\textrm{Cl}$ isotope will be '1 - x'

For $_{17}^{35}\textrm{Cl}$ isotope:

Mass of $_{17}^{35}\textrm{Cl}$ isotope = 34.9689 amu

Fractional abundance of $_{17}^{35}\textrm{Cl}$ isotope = x

For $_{17}^{37}\textrm{Cl}$ isotope:

Mass of $_{17}^{37}\textrm{Cl}$ isotope = 36.9659 amu

Fractional abundance of $_{17}^{37}\textrm{Cl}$ isotope = 1 - x

Average atomic mass of chlorine = 35.4527 amu

Putting values in equation 1, we get:

$35.4527=[(34.9689\times x)+(36.9659\times (1-x))]\\\\x=0.7577$

Percentage abundance of $_{17}^{35}\textrm{Cl}$ isotope = $0.7577\times 100=75.77\%$

Percentage abundance of $_{17}^{37}\textrm{Cl}$ isotope = $(1-0.7577)=0.2423\times 100=24.23\%$

Hence, the percentage abundance of $_{17}^{35}\textrm{Cl}$ and $_{17}^{37}\textrm{Cl}$ isotopes are 75.77% and 24.23% respectively.

6 0

3 years ago

How many electrons do all atoms want to have in their outer energy level?

34kurt

Answer: 8 electrons

Explanation:

4 0

2 years ago

The diagram below shows part of the rock cycle.

snow_lady [41]

The answer is igneous

5 0

3 years ago

Read 2 more answers

Please answer these questions

lions [1.4K]

I found number one
Atoms are not drawn to scale. Molecules of compounds have atoms of two or more different elements. For example, water (H2O) has three atoms, two hydrogen (H) atoms and one oxygen (O) atom. Methane (CH4), a common greenhouse gas, has five atoms, one of carbon (C) and four of hydrogen (H, see Fig.

7 0

3 years ago

Read 2 more answers