Chemical indicator, any substance that gives a visible sign, usually by a color change, of the presence or absence of a threshold concentration of a chemical species, such as an acid or an alkali in a solution.
Answer:
See explanation
Explanation:
The atoms of metals have fewer valence electrons than the atoms of metals and metalloids.
Atoms of metals have only very few valence electrons in their outermost shells hence they donate electrons during bonding. However, atoms of nonmetals have more electrons in their outermost shells and rather accept electrons during bonding. The atoms of metalloids just have a number of valence electrons that are intermediate between those of metals and nonmetals and mostly share electrons in covalent bonds.
Similarly, atoms of metallic elements differ from each other in the number of valence electrons present in the valence shell of the atom of each element. For instance, sodium has one electron in the valence shell of its atom while aluminium has three electrons in the valence shell of its atom.
Answer:3480s⁻¹
Explanation:We can solve the following problem using the Arrhenius equation.
Arrhenius equation is given by:
![K=Aexp[-Ea/RT]](https://tex.z-dn.net/?f=K%3DAexp%5B-Ea%2FRT%5D)
A=Pre-exponential factor or frequency factor
Ea=Activation energy
R=Ideal gas constant
T=Temperature
K=Rate constant
From the Arrhenius equation we can see that the rate constant K is related with the activation energy and frequency factor.
In the question we are given with the following data:
Ea=42KJ/mol=42x 1000 J/mol
A=8.0×10¹ per second
T=298K
R=8.314J/K mol
when we substitute these given values in Arrhenius equation
![K=A{exp[-Ea \div RT]}\\K=8\ \times10^{10} s^{-1}{exp[-42000\div 8.314\times298]}\\K=8\ \times10^{10} s^{-1}{exp[-16.95]}\\K=4.35\times10^{^{-8}}\times8.0\times10^{^{10}}s^{-1}\\K=34.8\times10^{2}s^{-1}\\](https://tex.z-dn.net/?f=K%3DA%7Bexp%5B-Ea%20%5Cdiv%20RT%5D%7D%5C%5CK%3D8%5C%20%5Ctimes10%5E%7B10%7D%20s%5E%7B-1%7D%7Bexp%5B-42000%5Cdiv%208.314%5Ctimes298%5D%7D%5C%5CK%3D8%5C%20%5Ctimes10%5E%7B10%7D%20s%5E%7B-1%7D%7Bexp%5B-16.95%5D%7D%5C%5CK%3D4.35%5Ctimes10%5E%7B%5E%7B-8%7D%7D%5Ctimes8.0%5Ctimes10%5E%7B%5E%7B10%7D%7Ds%5E%7B-1%7D%5C%5CK%3D34.8%5Ctimes10%5E%7B2%7Ds%5E%7B-1%7D%5C%5C)
K=3480s⁻¹
The value of rate constant obtained is 3480s⁻¹.
The best name for the compound is DINITROGEN TRIOXIDE.
Each chemical compound is always represented by a chemical symbol, which shows the ratio at which each atom of the elements of the compound are combine together and this is often used in naming the compound. Looking at the compound given in the question, the compound is made up of two atoms of nitrogen and three atoms of oxygen and this fact was used in naming the compound. In naming chemical compounds, 'Di' stands for 2 while 'Tri' stands for 3. Since there are two nitrogen and three oxygen atoms in the compound, that was why it was named dinitrogen trioxide.
Answer:
option b is the correct answer
