solid carbon dioxide, iodine, arsenic, and naphthalene
Explanation:
Examples of substances that undergo sublimation
Examples of solids that sublime are dry ice (solid carbon dioxide), iodine, arsenic, and naphthalene (the stuff mothballs are made of).
First convert to moles:
0.5113 g / 17 g/mol = 0.0301 mol
Now create a ratio based on the reaction provided to solve for the unknown:
4 NH3 / -905.4 kJ = 0.0301 mol NH3 / x kJ
x = -6.808 kJ
Without any ionization, the element (Cn) would have 112 electrons because the atomic number of an element is the number of protons the element has and a neutral element has the same number of electrons as it does protons.
Lower
Melting points of molecular solids are lower than melting points of ionic compounds
Answer: 3 significant figures
Explanation: because in scientific notation only the before and after decimal number are considered but in standard form all numbers including exponents are all significant figures
