Answer:
+1.03 V
Explanation:
The standard emf of the voltaic cell is the value of the standard potential of it, which is calculated by the standard reduction potential (E°).
The standard reduction potential is the potential needed for the reduction reaction happen, and it's determined by the reaction with the hydrogen cell (which has E° = 0.0V). The half-reactions of reduction of Ni⁺² and Ag⁺, are:
Ni⁺²(aq) + 2e⁻ → Ni(s) E° = -0.23 V
Ag⁺(aq) + e⁻ → Ag(s) E° = +0.80 V
The value is calculated by a spontaneous reaction, in which the cell with the greater E° is reduced (gain electrons), and the other is oxidized (loses electrons). So, Ag⁺ reduces.
emf = E°reduces - E°oxides
emf = 0.80 - (-0.23)
emf = +1.03 V
<u>Answer:</u> The correct option is d) 460 kJ
<u>Explanation:</u>
We are given:
Content of fat in energy drink = 2.0 g
Content of protein in energy drink = 6.0 g
Content of carbohydrate in energy drink = 16.3 g
Also,
The fuel value of fat = 38 kJ/g
The fuel value of protein = 17 kJ/g
The fuel value of carbohydrate = 17 kJ/g
So, the fuel value of the energy drink will be:
Total fuel value = 
Total fuel value = ![[76+102+277]=460kJ](https://tex.z-dn.net/?f=%5B76%2B102%2B277%5D%3D460kJ)
Hence, the correct option is d) 460 kJ
Answer:
there is no picture so we can't tell why the containers are heavy
<u>Answer:</u> The percentage abundance of
and
isotopes are 75.77% and 24.23% respectively.
<u>Explanation:</u>
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:
.....(1)
Let the fractional abundance of
isotope be 'x'. So, fractional abundance of
isotope will be '1 - x'
- <u>For
isotope:</u>
Mass of
isotope = 34.9689 amu
Fractional abundance of
isotope = x
- <u>For
isotope:</u>
Mass of
isotope = 36.9659 amu
Fractional abundance of
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](https://tex.z-dn.net/?f=35.4527%3D%5B%2834.9689%5Ctimes%20x%29%2B%2836.9659%5Ctimes%20%281-x%29%29%5D%5C%5C%5C%5Cx%3D0.7577)
Percentage abundance of
isotope = 
Percentage abundance of
isotope = 
Hence, the percentage abundance of
and
isotopes are 75.77% and 24.23% respectively.
Answer:
a) alkali metals
Explanation:
The element described above definitely belonged to the alkali metals, the first group on the periodic table. They show the properties indicated in the text.
- They are metals because only metals are lustrous and malleable. This eliminates the possibility of them being halogens and noble gases.
- Only group 1 metals reacts vigorously with water to form alkali.
- Alkali are aqueous solutions that are basic in nature.
- The reactivity of group 1 metals is due to their one extra electrons in the outer most shell.
- These electrons are easily and readily lost in order for such atoms to gain stability and replicate the nearest noble gases.
- The most reactive metal belongs to this group elements.
- This is why it is nearly impossible to find them occurring alone in free state.
- Some of the elements in this group are Li, Na, K, Rb, Cs and Fr.
- Transition metals have variable oxidation states and some can be found alone in nature.