Nonmetals usually exist as molecules, combining with atoms of themselves.
Nonmetals can exist on their own as individual atoms.
Metallic elements can exist on their own as individual atoms.
Explanation:
Non-metals usually exists as molecules in which their atoms combines with one another.
Non-metals are capable of covalently bonding with themselves by sharing their electrons and establishing an atomic bond. Metals cannot do this because they prefer to lose their electrons due to the large density of electrons in them. For example O₂, N₂ e.t.c
Non-metals can exist on their own as individual atoms. A stable atom with an octet configuration is generally stable and can exist on its own. A group of non-metals in group 8 can exist on their own. For example Neon gas is an atom of neon, Argon e.t.c
Metallic elements can also exists as individual atoms on their own. They have large sizes and prefers to lose electrons. Gold, Copper, Sodium are some of the metallic elements freely occur as stable individual atoms.
Learn more:
Metals and non-metals brainly.com/question/2758034
Properties of metals brainly.com/question/2474874
#learnwithBrainly
Answer:
40 Hz
Explanation:
f = 1/T = 1 / 0.025 = 40 Hz
Answer:
a) P=0.25x10^-7
b) R=B*N2*E
c) N=1.33x10^9 photons
Explanation:
a) the spontaneous emission rate is equal to:
1/tsp=1/3 ms
the stimulated emission rate is equal to:
pst=(N*C*o(v))/V
where
o(v)=((λ^2*A)/(8*π*u^2))g(v)
g(v)=2/(π*deltav)
o(v)=(λ^2)/(4*π*tp*deltav)
Replacing values:
o(v)=0.7^2/(4*π*3*50)=8.3x10^-19 cm^2
the probability is equal to:
P=(1000*3x10^10*8.3x10^-19)/(100)=0.25x10^-7
b) the rate of decay is equal to:
R=B*N2*E, where B is the Einstein´s coefficient and E is the energy system
c) the number of photons is equal to:
N=(1/tsp)*(V/C*o)
Replacing:
N=100/(3*3x10^10*8.3x10^-19)
N=1.33x10^9 photons
Heat required to raise the temperature of water is given as
here we have
m = 100 g = 0.100 kg
s = 4183 J/kg C
now we can use the above equation
so here it requires 20920 J heat to raise the temperature of 100 g water by 50 degree C
