0.0024 g of Ba(NO₃)₂
Explanation:
First we need to determine the molecular weight of barium nitrate Ba(NO₃)₂
molecular wight of Ba(NO₃)₂ = molecular weight of Ba × number of Ba atoms + molecular weight of N × number of N atoms + molecular weight of O × number of O atoms
molecular wight of Ba(NO₃)₂ = 137 × 1 + 14 × 2 + 16 × 6 = 261 g/mol
number of moles = mass / molecular weight
mass = number of moles × molecular weight
mass of Ba(NO₃)₂ = 0.625 / 261 = 0.0024 g
Learn more about:
moles
brainly.com/question/10392090
brainly.com/question/1445383
#learnwithBrainly
Answer:
An alkali metal present in period 2 have larger first ionization energy.
Explanation:
Ionization energy:
The amount of energy required to remove the electron from the atom is called ionization energy.
Trend along period:
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction. The electrons are pull towards the nucleus and valance shell get closer to the nucleus. As a result of this greater nuclear attraction atomic radius decreases and ionization energy increases because it is very difficult to remove the electron from atom and more energy is required.
Trend along group:
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
As the size of atom increases the ionization energy from top to bottom also decreases because it becomes easier to remove the electron because of less nuclear attraction and as more electrons are added the outer electrons becomes more shielded and away from nucleus. Thus alkali metal present in period 2 have larger ionization energy because of more nuclear attraction as compared to the alkali metal present in period 4.
Answer:
f = V / λ
Explanation:
In this formula, f represents frequency, V represents the velocity of the wave, and λ represents the wavelength of the wave
Answer:
Wheel and axles
Explanation:
Clocks run on a complex system of gear trains. This provides the energy to turn the hands of the clock. A high-ratio gear train gears the weight drum way up so that you don't have to rewind the clock very often. This somehow disengages, slips or ratchets the gear train so the clock can be rewound and set.
It allows scientists to visualize the molecule they are working with more vividly.
It also allows them to see the ratio of atoms It contains which further allows
scientist to find the proportions of chemicals to mix together to maximize the
efficiency of a chemical reaction.