When mantle rocks near the radioactive core are heated, they become less dense than the cooler, upper mantle rocks. these warmer rocks rise, while the cooler rocks sink. this movement of warmer and cooler mantle rocks creates pockets of circulation within the mantle called which are thought to be the force behind the movement of tectonic plates over the asthenosphere.
a) magma flows
b) density cells
c) convection cells (currents)
d) conduction points

chemistry sucks a**

explanation:

water at room temperature is flowing through a pipe with pressure taps located 10 ft apart along one section of the pipe, which are connected to a mercury (s=13.6) manometer.

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.

the seeing the electronic configuration we can say that the element is fluorine.

fluorine is the most electronegative element in the periodic table.

but by only seeing the configuration we cannot say about its reactivity because we don't know if its configuration after excitation or by addition of electrons.

but if not then, it is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. as the most electronegative element, it is extremely reactive: almost all other elements, including some noble gases, form compounds with fluorine.