Galaxy Formation. One says that galaxies were born when vast clouds of gas and dust collapsed under their own gravitational pull, allowing stars to form. The other, which has gained strength in recent years, says the young universe contained many small "lumps" of matter, which clumped together to form galaxies.
The formula of work is Work (Joules)=Force (Newtons) · distance in the direction of the force (meters), therefore its just a matter of replacing factors.
Work done = 12 · 4.5= 54 joules
The reaction of acid, assuming HCl and calcium carbonate always produces a gas. The reaction is as follows:
2 HCl + CaCO3 --> CaCl2 + H2CO3
H2CO3, carbonic acid, is a weak acid that is unstable in water solutions at high concentrations. As such, it decomposes:
H2CO3 --> H2O + CO2
Then,
2 HCl + CaCO3 --> CaCl2 + H2O + CO2
The total ionic equation looks as follows:
2H+(aq) + 2 Cl-(aq) + CaCO3(s) --> Ca+2(aq) + 2 Cl-(aq) + H2O(l) + CO2(g)
Clearly, Cl- is a spectator ion as it is unchanged in the reaction. The net ionic reaction looks as follows:
2 H+(aq) + CaCO3(s) --> Ca+2(aq) + H2O(l) + CO2(g)
The colored light emitted is energy and in order to emit energy the element should first obtain energy. The energy absorbed by the substance can be in the form of radiation, heat or electricity. Hope this answers the question. Have a nice day.
The conversion of volume to moles at STP is 1 mole.
The ideal gas equation is given as :
P V = n R T
where,
P = pressure of the gas
V = volume of the gas
n = ?
R = constant = 0.823 atm L / mol K
T = temperature
At STP , the pressure is 1 atm and the temperature is 273.15 K, the volume At STP is 22.4 L.
moles , n = P V / R T
n = ( 1 × 22.4 ) / (0.0823 × 273.15)
n = 1 mole
Thus, at STP , the number of moles is 1 mol.
To learn more about moles here
brainly.com/question/8429153
#SPJ4