The answer is d I'm pretty sure because the second one and the first one don't make sense but I'm not 100 percent positive about it not being d ..... sorry if it's wrong.
The correct answer is option B. X-rays are the waves found in the electromagnetic spectrum at a wavelength of 1x10^-11 - 1x10^-8 m and frequencies of 3x10^16 to 3x10^19 Hz. These waves penetrate easily through certain materials which made them usefule in the field of medicine.
When E° cell is an electrochemical cell which comprises of two half cells.
So,
when we have the balanced equation of this half cell :
Al3+(aq) + 3e- → Al(s) and E°1 = -1.66 V
and we have also this balanced equation of this half cell :
Ag+(aq) + e- → Ag(s) and E°2 = 0.8 V
so, we can get E° in Al(s) + 3Ag (aq) → Al3+(aq) + 3Ag(s)
when E° = E°2 - E°1
∴E° =0.8 - (-1.66)
= 2.46 V
∴ the correct answer is 2.46 V
Answer:
1.5055×10²⁴ molecules
Explanation:
From the question given above, the following data were obtained:
Number of mole CO₂ = 2.5 moles
Number of molecules CO₂ =?
The number of molecules present in 2.5 moles CO₂ can be obtained as:
From Avogadro's hypothesis,
1 mole of CO₂ = 6.022×10²³ molecules
Therefore,
2.5 mole of CO₂ = 2.5 × 6.022×10²³
2.5 mole of CO₂ = 1.5055×10²⁴ molecules
Thus, 1.5055×10²⁴ molecules are present in 2.5 moles CO₂
Answer:
The symbol of the ion is A^-
Explanation:
Let A be the symbol of the element.
Proton = 17
Electron = 18
Neutron = 20
Since the element has more electrons than protons, it means it has gain electrons.
From the question given,
The difference between the electron and proton = 18 — 17 = 1
So, the element has gain 1 electron.
Therefore the symbol of the ion is A^-
