Calculate the H positive from the pH equation: pH equals -log (H positive). This would be 10 to the -6.49. Let's call the acid HA. To calculate Ka in this equation, Ka equals H positive times A- over HA. HA is going to be the 0 0121. So, Ka=(10^-6.49)^2/0.0121. This equals 1.05*10^-13/0.0121. Ka then equals 8.65*10^-12.
Answer:
A compound
Explanation:
A compound is a pure substance that contains atoms of more than one element.
For example, water is a compound.
It is pure because it consists only of water molecules, and each molecule contains atoms of the elements hydrogen and oxygen.
Before the periodic table, there were a bunch of symbols, number, letters etc (In all kinds of languages) that represented the elements. Scientists around the world saw that a chart of the elements needed to be universally accepted and finalized. A guy named Mendeleev presented this idea to the scientific community. Mendeleev was also the first to order elements according to atomic number rather than atomic weight. The modern day periodic table was not published by him, it was developed with the help of the entire scientific community. Honestly, there isn't a specific way to tell you how the periodic table was constructed, scientists developed thousands of tables that represented the elements. And just to let you know, the modern day periodic table is constantly going through changes as we discover more and more about elements, atoms, molecules etc. so in the near future it wouldn't be surprising if we saw something completely different than what we see today.
Answer:
a) water molecules move rapidly in the mug of boiling water while they move slowly in the ice water. In the ice itself, the molecules stay in place.
b) Water must release energy to move from a higher to lower energy phase, i.e., from gas (water) vapor to liquid during condensation and from liquid to solid (ice) during freezing. In each case, the energy released by the water results in a change in the internal molecular bonding structure.
Explanation:
