Answer:
7.0*10-11m or 70Å
Explanation:
From Bragg's equation, w=2dsinx/n
Since all the parameters are specified in the question, we can easily go ahead to obtain the wavelength but we must convert the spacing given in angstroms to meters using the conversion factor provided as shown in the solution below:
Answer:
The electron configuration for this atom is Calcium, which has 2 valence electrons.
Explanation:
Following the periodic table and with the electron configuration, you will end up with calcium, which has 2 valence electrons. (Always follow the electron configuration from left to right! It begins at hydrogen, then to helium... and so on.)
1s2 -> He....
2s2 -> Be....
2p6 -> Ne...
3s2 -> Mg...
3p6 -> Ar...
4s2 -> Ca.
A chemical reaction (signs)
- rusting
- change in base of chemical
- for example lets say u mix two chemicals, and then it becomes a different new chemical (it changed from the inside)
a physical
- a physical reaction is outer looks not inside.
- it changes on the outside, like changing a color
Answer:
a. minimum voltage that must be supplied for a redox reaction to occur
c. always equal to Eanode - Ecathode
Explanation:
In an electrolytic cell; The electromotive force(the maximum standard potential difference) of the cell formed by the system is defined as the standard electrode potential of the right handed electrode minus the standard electrode potential of the left hand electrode. (i.e 
)
As we all known that the process by which chemical energy is being converted to electrical energy is called the Electrochemical cell. It consists of two half cells , an oxidation half cell reaction and a reduction half-cell reaction.The overall redox reaction results in a flow of electrons in an electric current which is produced by a minimum voltage.
Therefore, option a and c are both correct.
C. quadruples the rate
<h3>Further explanation</h3>
Given
The rate law :
R=k[A]²
Required
The rate
Solution
There are several factors that influence reaction kinetics :
- 1. Concentration
- 2. Surface area
- 3. Temperature
- 4. Catalyst
- 5. Pressure
- 6. Stirring
The rate is proportional to the concentration.
If the concentration increased, the reaction rate will increase
The reaction is second-order overall(The exponent is 2)
The concentration of A is doubled, the reaction rate will increase :
r = k[A]² ⇒ r= k[2A]²⇒r=4k[A]²
<em>The reaction rate will quadruple.</em>
