Answer:
1) Ba(OH)₂
2) The correct option is a) they conduct electricity.
Explanation:
To deduce the formula of Barium hydroxide, we have to go to the periodic table and look for the Barium (Ba), which is in group 2 and has an ionic charge of 2+. Hydroxides are not an element that is present in the periodic table is the combination of Oxygen and Hydrogen (OH), and its ionic charge is 1-.
To name this substance, we write the elements that form it, which are Ba OH, then we see the ionic charges that they have, Ba2+ OH 1- and we change these charges giving the 2+ to the OH and the 1- to the Ba. It would look Ba OH₂; we do not write the 1, and as there is a 2, the OH, has to be between brackets so that the final formula is Ba(OH)₂. What we did is balancing the charges of the elements. In other words, we need 2 OH for every Ba. Hydroxides give an electron to balance the Ba ionic charge.
Barium Hydroxide is an ionic compound because ionic compounds are formed by a metal (Ba) and a nonmetal element (OH), ionic compounds are charged, so when they are in an aqueous solution they conduct electricity because their ions move freely in the solution.
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C) medium.
The medium of a wave is any substance that carries the wave, or through which the wave travels.Ocean waves are carried by water, sound waves are carried by air, and. the seismic waves of an earthquake are carried by rock and soil.
<h2>Answer : Option B) Ozone</h2><h3>Explanation :</h3>
The layer of atmosphere which contains a substance(Ozone) that was created from a product of living thins (oxygen) and protects living things (from harmful UV rays).
Oxygen in the atmosphere reacts in presence of UV rays and forms Ozone.
This ozone forms a protective layer around the earth and protects it from harmful UV rays.
117.22 g are needed to react with an excess of Fe2O3 to produce 156.2 g of Fe.
Explanation:
Moles of Fe = Mass of Fe in grams / Atomic weight of Fe
= 156.2 / 55.847
Moles of Fe = 2.79.
The ratio between CO and Fe id 3 : 2.
Moles CO needed = 2.79 * (3 / 2)
= 4.185.
To calculate Atomic weight of CO,
Atomic weight of carbon = 12.011
Atomic weight of oxygen= 15.9994
Atomic weight of CO = 12.011 + 15.9994 = 28.01 g / mol.
Mass of CO = 4.185 * 28.01 = 117.22 g.
