1.For each of the following, give the name of an element from Period 4 (potassium to krypton), which matches the description.
Elements may be used once, more than once or not all.. Single line text.
(1 Point)
an element that reacts with water to produce a lilac flame
2.For each of the following, give the name of an element from Period 4 (potassium to krypton), which matches the description.
Elements may be used once, more than once or not all.. Single line text.
(1 Point)
an element used as an inert atmosphere
3.For each of the following, give the name of an element from Period 4 (potassium to krypton), which matches the description.
Elements may be used once, more than once or not all.. Single line text.
(1 Point)
an element that has a valency of 3
4.Write a balanced chemical equation for the reaction between potassium and water. (Non-anonymous question). .
(1 Point)
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5.For each of the following, give the name of an element from Period 4 (potassium to krypton), which matches the description.
Elements may be used once, more than once or not all.. Single line text.
(1 Point)
an element with a fixed valency of 2 that not is not in group 2
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Answer:
333K
Explanation:
Answer is actually 333.15, but to round it off, is 333
<span>5.45 x 10^3 kg of sodium carbonate is needed to neutralize 5.04 kg of sulfuric acid.
For this, I will assume you have pure H2SO4. So first, you need to calculate the molar mass of H2SO4 and Na2CO3. Lookup the atomic weights of all the elements involved.
Atomic weight of Sodium = 22.989769
Atomic weight of Sulfur = 32.065
Atomic weight of Carbon = 12.0107
Atomic weight of Oxygen = 15.999
Atomic weight of Hydrogen = 1.00794
Molar mass of H2SO4 = 2 * 1.00794 + 32.065 + 4 * 15.999 = 98.07688 g/mol
Molar mass of Na2CO3 = 2 * 22.989769 + 12.0107 + 3 * 15.999
= 105.987238 g/mol
The balanced equation for the reaction of Na2CO3 with H2SO4 is
Na2CO3 + H2SO4 => Na2SO4 + CO2 + H2O
so for every mole of sulfuric acid to be neutralized, you need 1 mole of sodium carbonate. You can determine the number of moles of sulfuric acid you have and then calculate the mass of that many moles of sodium carbonate. But, there's an easier way. Just use the relative mass differences between sodium carbonate and sulfuric acid. So
105.987238 g/mol / 98.07688 g/mol = 1.080655
So that means for every kg of sulfuric acid, you need 1.080655 kg of sodium carbonate. Now do the multiplication.
5.04 x 10^3 kg * 1.080655 = 5.4465 x 10^3 kg.
Since you only have 3 significant figures for your data, round the result to 3 significant figures, giving 5.45 x 10^3 kg</span>
Answer:
The energy of the photon is 
.
Explanation:
Given:
The wavelength of the photon is given as:
The energy of a photon in terms of its wavelength is given as:
Plug in all the given values and calculate energy of the photon, 
. This gives,
Therefore, the energy of the photon is .
Answer mgjvguvjngujgguhggj
