The empirical formula : Na₂Cr₂O₇
<h3>Further explanation</h3>
Given
170 g sample contains :
29.84 g sodium, 67.49 g chromium, and 72.67 g oxygen
Required
The compound's empirical formula
Solution
mol ratio of elements :
Na : 29.84 : 23 g/mol = 1.297
Cr : 67.49 : 51,9961 g/mol = 1.297
O : 72.67 : 16 g/mol = 4.54
Divide by 1.297
Na : Cr : O = 1 : 1 : 3.5 = 2 : 2 : 7
Answer:
shorter
longer
Explanation:
The carbon-carbon bond length in ethylene is <u>shorter</u> than the carbon-carbon bond length in ethane, and the HCH bond angle in ethylene is <u>longer</u> the HCH bond angle in ethane.
The objective of this question is to let us understand the concept of Bond Length and Bond angle among the unsaturated aliphatic hydrocarbons (i.e alkanes, alkenes and alkynes).
The variation in bond angles of unsaturated aliphatic hydrocarbons can be explained by two concepts; The valence shell electron pair repulsion (VSEPR) model and hybridization.
The VSEPR model determines the total number of electron pairs surrounding the central atom of a species. The total number of electron pairs consist of the bond pairs and lone pairs. All the electron pairs( lie charge ) will then orient themselves in such a way to minimize the electrostatic repulsion between them.
As the number of the lone pairs increases from zero to 2 ; the bond angles diminish progressively.
However;
Hybridization is the mixing or blending of two or more pure atomic orbitals (s,p and d) to form two or more hybrid atomic orbitals that are identical in shape and energy . e.g sp, sp² , sp³ hybrid orbitals etc .
The shape of the geometry of this compound hence determines their bond angle.
The shape of the geometry of ethane is tetrahedral which is 109.5° in bond angle while that of ethylene is trigonal planar which is 120°.
This is why the HCH bond angle in ethylene is longer the HCH bond angle in ethane .
Answer:
The answer to your question is pH = 9.2; [OH] = 1.58 x 10⁻⁵
Explanation:
Data
[H⁺] = 6.0 x 10⁻¹⁰ M
pH = ?
pH definition. pH measures the hydrogen concentration. pH measures the acidity and the alkalinity of a solution. A solution is acid if the pH goes from 0 to 6.9, a neutral solution has a pH of 7 and an alkali solution has a pH from 7.1 to 14.
pOH measures the [OH⁻] concentration
Formula
pH = -log[H⁺]
pH + pOH = 14
-Substitution
pH = -log[6 x 10⁻¹⁰]
-Simplification
pH = - (-9.2)
pH = 9.2
-Calculate pOH
pOH = 14 - pH
pOH = 14 - 9.2
pOH = 4.8
-Calculate the concentration of OH⁻
pOH = -log[OH⁻]
[OH⁻] = -antilog4.8
[OH] = 1.58 x 10⁻⁵
The fourth most abundant element in terms of mass is Carbon.
The first, second, and third most abundant element in terms of mass are Hydrogen, Helium, and Oxygen, respectively.
Hope this helps~
Crystallization is a physical change from liquid form to solid form. It is the opposite of melting. This is done by creating a supersaturated solution. You add more solute exceeding its capacity and heat so that all will dissolve. Then, when you cool it down with an aid of the ice, solid crystals will eventually form. The bigger the container the ice, the faster is the rate of crystallization and the bigger the solid crystals would be.
