Answer: Heating the hydrated forms of cobalt chloride reverses the reactions above, returning cobalt chloride to the blue, water-free, or anhydrous, state. Water is "liberated" in these reactions, known as dehydration reactions.
Explanation:
<span>361.4 pm is the length of the edge of the unit cell.
First, let's calculate the average volume each atom is taking. Start with calculating how many moles of copper we have in a cubic centimeter by looking up the atomic weight.
Atomic weight copper = 63.546
Now divide the mass by the atomic weight, getting
8.94 g / 63.546 g/mol = 0.140685488 mol
And multiply by Avogadro's number to get the number of atoms:
0.140685488 * 6.022140857x10^23 = 8.472278233x10^22
Now examine the face-centered cubic unit cell to see how many atoms worth of space it consumes. There is 1 atom at each of the 8 corners and each of those atoms is shared between 8 unit cells for for a space consumption of 8/8 = 1 atom. And there are 6 faces, each with an atom in the center, each of which is shared between 2 unit cells for a space consumption of 6/2 = 3 atoms. So each unit cell consumes as much space as 4 atoms. Let's divide the number of atoms in that cubic centimeter by 4 to determine the number of unit cells in that volume.
8.472278233x10^22 / 4 = 2.118069558x10^22
Now calculate the volume each unit cell occupies.
1 cm^3 / 2.118069558x10^22 = 4.721280262x10^-23 cm^3
Let's get the cube root to get the length of an edge.
(4.721280262x10^-23 cm^3)^(1/3) = 3.61426x10^-08 cm
Now let's convert from cm to pm.
3.61426x10^-08 cm / 100 cm/m * 1x10^12 pm/m = 361.4 pm
Doing an independent search for the Crystallographic Features of Copper, I see that the Lattice Parameter for copper at at 293 K is 3.6147 x 10^-10 m which is in very close agreement with the calculated amount above. And since metals expand and contract with heat and cold, I assume the slight difference in values is due to the density figure given being determined at a temperature lower than 293 K.</span>
Answer: e. Two of these
Explanation:
(a) 
When is dissolved in water. It reacts to form sulfurous acid. The chemical reaction is shown below:
Therefore, is acidic when dissolved in water.
(b) 
When is dissolved in water. It reacts to form nitric acid. The chemical reaction is shown below:
Therefore, is acidic when dissolved in water.
(c) 
Sodium is a metal. It gives sodium hydroxide on reaction with water. The chemical reaction is as follows:
Therefore, Na is basic when dissolved in water.
(d) 
Calcium oxide is a metallic salt. It gives calcium hydroxide on reaction with water. The chemical reaction is as follows:
,
Therefore, is basic when dissolved in water.
(e) Two of these.
Since both and give acids when dissolved in water, both are acidic.
Answer:
2 atoms of carbon combine with 6 atoms of hydrogen to from ethane.
<span>The balanced equation is: C3H8 + 5 O2 = 3 CO2 + 4 H2O
</span>1) first step is to<span> determine the molar mass you have to consult the periodic table and see the atomic mass of each element. If the element is repeated, for example 3 times, you multiple the atomic mass per 3.
C3H8= 12 x 3 + 1*8
= 44 g/mol
2)convert grams to moles so that everything will be in same unit.</span>
<span>moles are calculated by dividing mass by molar mass.
moles of C3H8= 295g / 44 g/mol
= 6.705 mol
3)By looking at the balanced equation, you can see that 1 mol of C3H8 will produce 3 moles of CO2. So if you have 6,705 moles, you will obtain x moles of CO2:
1 C3H8--------3 CO2
6,705----------x of CO2
x= 20,115 mol of CO2
</span>
4) At STP(<span>Standard Temperature and Pressure)</span> 1 mole of gas is equivalent to 22.4 liters.
1 mol of CO2-----22,4
20,115 -------------x liters
x= 20,115 x 22,4 =
450,6 liters.
