The complete answer contains the answer choices.
This is the complete question:
Atoms of which element react spontaneously with Mg2+(aq)? (1)chromium
(2)barium
(3)iron
(4)zinc
Answer: option 2. barium.
Explanation.
1) Mg ²⁺ (aq) is the aquous cation of the metal Mg.
2) Only a metal more reactive than Mg will be able to exchange with it the oxidation states.
3) Mg is an earth alkalyne metal (group 2 of the periodic table). The metals from this group are more reactive than the metals in the groups to its right: 3, 4, 5, 6, 7, ... Only the alkalyne metals (those in group 1) are more reactive than the earth alkalyne metals.
4) Of the list, barium is the only alkalyne metal, so it is more reactive than Mg and will be able to deliver 2 electrons to transform the cations Mg²⁺ into Mg while the very Ba will become Ba²⁺.
5) Chromium, iron and zinc are transition metals, so less metallic (reactive) than Mg.
Answer:
D. Cyclic alkane
Explanation: there is no double or triple bond
CS2 + 3O2 = CO2 + 2SO2
1 mole of CS2 gives 1 mole of CO2
12 + 2(32) = 76g of CS2 yields 44 g of CO2
Theoretically 1 g of CS2 yields 44/76 g CO2
Therefore 50 g CS2 should yield 50*44 / 76 = 28.95 g
So % yield = 103.6 % ( which is not possible because you can't create matter from nothing).
The 30g cannot be right . This is experimental err.
<span>C2H5
First, you need to figure out the relative ratios of moles of carbon and hydrogen. You do this by first looking up the atomic weight of carbon, hydrogen, and oxygen. Then you use those atomic weights to calculate the molar masses of H2O and CO2.
Carbon = 12.0107
Hydrogen = 1.00794
Oxygen = 15.999
Molar mass of H2O = 2 * 1.00794 + 15.999 = 18.01488
Molar mass of CO2 = 12.0107 + 2 * 15.999 = 44.0087
Now using the calculated molar masses, determine how many moles of each product was generated. You do this by dividing the given mass by the molar mass.
moles H2O = 11.5 g / 18.01488 g/mole = 0.638361 moles
moles CO2 = 22.4 g / 44.0087 g/mole = 0.50899 moles
The number of moles of carbon is the same as the number of moles of CO2 since there's just 1 carbon atom per CO2 molecule.
Since there's 2 hydrogen atoms per molecule of H2O, you need to multiply the number of moles of H2O by 2 to get the number of moles of hydrogen.
moles C = 0.50899
moles H = 0.638361 * 2 = 1.276722
We can double check our math by multiplying the calculated number of moles of carbon and hydrogen by their respective atomic weights and see if we get the original mass of the hydrocarbon.
total mass = 0.50899 * 12.0107 + 1.276722 * 1.00794 = 7.400185
7.400185 is more than close enough to 7.40 given rounding errors, so the double check worked.
Now to find the empirical formula we need to find a ratio of small integers that comes close to the ratio of moles of carbon and hydrogen.
0.50899 / 1.276722 = 0.398669
0.398669 is extremely close to 4/10, so let's reduce that ratio by dividing both top and bottom by 2 giving 2/5.
Since the number of moles of carbon was on top, that ratio implies that the empirical formula for this unknown hydrocarbon is
C2H5</span>
Answer:
Explanation:
The period law state that when elements are listed in order of their atomic numbers, the elements fall into recurring groups, so that there is a recurrence of similar properties at regular intervals.
Na and K in the periodic table fall into the same group, this is because they both have one electrons in their outermost shell.
Na 11 -1s2 2s2 2p6 3s1
K 19 - 1s2 2s2 2p6 3s2 3p6 4s1
They share similar chemical and physical properties. Na and K are very reactive metals, they can loose/donate their outermost electron to non metals in other to attain stable octet state.
The form ionic compound when they react with non metals.
