Answer:

Explanation:
Assuming that all caculations are at normal pressure and -1.72°C :

Where
is the number of moles of hydrogen
is the mass of hydrogen
is the density of hydrogen
<span>A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds. The bond may result from the electrostatic force of attraction between oppositely charged ions as in ionic bonds; or through the sharing of electrons as in covalent bonds. The strength of chemical bonds varies considerably; there are "strong bonds" or "primary bond" such as metallic, covalent or ionic bonds and "weak bonds" or "secondary bond" such as Dipole-dipole interaction, the London dispersion force and hydrogen bonding.</span>
An SI base unit for measuring length would be meters.
Answer:
Vinegar contains acetic acid which removes this coating. When the protective coating is removed, oxygen in the atmosphere can reach the iron in the steel wool and a chemical reaction called oxidation occurs. ... This reaction is also an exothermic reaction. It creates heat energy
Explanation:
hope this helps u
<span>
Phenobarbital is derivative of
Barbituric Acid and Barbituric Acid is derivative of
Urea. (structures shown in Fig below)
Urea has H</span>₂N- group attached to Carbonyl Group (C=O), and such class of comounds conataining H₂N-C=O bond are called as Amides.
Result: So, <span>Phenobarbital belongs to
Amides.</span>