Answer:
Hoà tan 20,8g BaCl2 vào nước được 0,5l dung dịch. Nồng độ của ion Cl- trong dung dịch?
Metallic and non-metallic properties
Non-metallic property increases across a period and decreases down the group due to the same reason due to an increase in nuclear attractive force.
I hope this helps
Answer:
1. A mole is the amount which contains as many elementary particles as there are atoms in 12 grams of carbon-12. It is also the unit used in measuring the amount of matter. A mole also refers to the Avogadro's number of particles present in any substance.
2. 1mole of NaOH contains 6.02x10^23 atoms.
Therefore, 3.8 moles of NaOH will contain = 3.8 x 6.02x10^23 = 2.288 x 10^24 atoms
3. Molar Mass of Ca(OH)2 = 40 + 2(16+1) = 40 2(17) = 40 + 34 = 74g/mol
Explanation:
Answer : The energy of the photon emitted is, -12.1 eV
Explanation :
First we have to calculate the orbit of hydrogen atom.
Formula used :
where,
= energy of orbit
n = number of orbit
Z = atomic number of hydrogen atom = 1
Energy of n = 1 in an hydrogen atom:
Energy of n = 2 in an hydrogen atom:
Energy change transition from n = 1 to n = 3 occurs.
Let energy change be E.
The negative sign indicates that energy of the photon emitted.
Thus, the energy of the photon emitted is, -12.1 eV
Percent error is an expression that is used as a tool for determining the precision of your calculations. It is calculated by the absolute value of the difference of experimental and theoretical values over the theoretical values multiplied by 100%. Hope this helps.