Answer:
Because it has a quickly sedative effect and it has antimicrobial effect.
Explanation:
This gas is useful because is used to trait pain, reduce anxiety and promote relaxation, slow down the body reaction, so the dentist can use it to calm down the patients.
If the patient present some injuries, this gas can help in wound healing.
Answer:
A
Explanation:
The iron corrodes so it oxidized
Explanation:
Contributing structures are the resonating structures which are formed due to the delocalization of electrons in a molecule.
The azide ion that is 
, is a symmetrical ion, all of whose contributing structures have formal charges.
Lone pair of central nitrogen atom in azide ion is in conjugation with the neighboring nitrogen atoms.
Contributing structures of azide ion are drawn in the image attached.
From the equation q=mCΔT, set the q of copper = to q of water,
So --- mCΔT(copper)=mCΔT(water).
mass (Cu - copper) = 38g
mass (H2O - water) = 15g
C (H2O) = 4.184 J/g*C
ΔΤ (H2O) = 33-22 = 11*C
ΔΤ (Cu) = 33-80 = -47*C (the final temp is the same for both materials - thermal equilibrium)
C (Cu) = ?
So --- 38(-47)C[Cu]=15(4.184)(11)
--- C[Cu]=690.36/(-1786) = 0.3865 J/g*C, or 0.39 in 2 sig figs. (The negative goes away, because specific heats are usually positive)
