The percent composition of a non ironic solute is 40%c 6.7%H and 53.3%O. If a solution containing 2.90g of this substance 106g of water freezes at 0.41°C Calculate the molecular formula of the substance

Idon’t understand this page, can someone ?

The table lists the lattice energies of some compounds. compoundlattice energy (kj/mol)lif            –1,036licl            –853naf            –923kf            –821nacl            –786which statement about crystal lattice energy is  best  supported by the information in the table? the lattice energy increases as cations get smaller, as shown by lif and kf. the lattice energy increases as the cations get larger, as shown by lif and licl. the lattice energy decreases as cations get smaller, as shown by nacl and naf. the lattice energy decreases as the cations get smaller, as shown by naf and kf.

The chemical formula for emerald is be3al2(sio3)6.an emerald can be decided as