The first one is D hope it helps!
Well they would definitely rip up the flooring and replace it
Standard temperature and pressure (STP) means a temperature of 0°c and a pressure of 1 atmosphere (atm). The molar gas volume is used to convert between the number of moles of a gas and the volume of the gas at STP. One mole of a gas occupies a volume of 22400 cm³ or 22.4 liters at STP according to the molar gas volume.
Ionization Energy: DOWN a Group: Ionization energy DECREASES as you go DOWN a Group because the farther the valence electrons are from the nucleus (pulling power of the protons) the less energy it costs another atom to steal them
Answer:
B. PROTONS EXHIBIT STRONGER PULL ON OUTER f ORBITALS
Explanation:
Lanthanide contraction is the greater than normal decrease in the ionic radius of the lanthanide series from atomic number 57 to atomic number 71. This decrease is rather not expected of the ionic radii of these elements and they result in the greater decrease in the subsequent series of the lanthanides from the atomic number 72. The cause of which is as a result of the poor shielding effects of the nuclear charge around the electrons of the f orbitals. So therefore, protons are strongly pulled out of the 4f orbital and as a result of the poor shielding effect which causes the electrons of the 6s orbitals to be drawn more closer to the nucleus and hence resulting in a smaller atomic radii. It is worthy to note that the shielding effects of the inner electrons decreasing from s orbital to the f orbital; that is s > p > d > f. So from the decrease in the shielding effects from s to the f orbitals, lanthanide contraction results from the inability of the orbitals far away from s like the 4f orbiatls to shield the outermost shells of the lanthanide elements. So the cause of lanthanide contraction is the action of the protons which strongly pull the electrons of the f orbitals because of the poor shielding effects due to the distance of this orbital from the nucleus.
