How many people were considered undernourished in Latin America and the Caribbean in 2018?

Andrew [12]

To do this, you would first add together the molar mass of all involved elements, to find how many grams are in a mole of Cu(OH)2. Keep in mind, the molar mass is equal to the atomic mass of an element in grams. For example the molar mass of copper (Cu) would be 63.55 (with 2 sig. figs.)

Therefore, now we add together the mass of all elements involved.

Cu: (63.55)+O2(15.99x2=31.98)+H2(1.01x2=2.02)

63.55+31.98+2.02= 97.55g per mole of Cu(OH)2.

Now, divide what we have by how much it takes to get a mole of the stuff.

68.1/97.55= 0.698mol Cu(OH)2

6 0

3 years ago

A cylinder of iron has a mass of 23.45 g. If it is placed on an electronic balance that reports all masses 18.00% too low due to

frez [133]

A cube has a volume of 8.0 cm3 and a mass of 21.6 grams. ... using an electronic analytical balance. ... graduated cylinder ... The density of iron is 7.87 g/mL.

7 0

4 years ago

Hydrogen reacts with 0.771 g of carbon to form 0.90 g of a compound. What is the mass percent of hydrogen in the compound

morpeh [17]

Answer: 14.3%

Explanation: In order to find the mass percent of hydrogen in this compound, you must determine how many grams of hydrogen you'd get in 100 g of compound.

In your case, you know that an unknown mass of hydrogen reacts with 0.771 g of carbon to form 0.90 g of hydrocarbon, which is a compound that contains only carbon and hydrogen.

Use the total mass of the hydrocarbon to determine how many grams of hydrogen reacted with the carbon.

Now, if 0.90 g of this compound contain 0.129 g of hydrogen, it follows that 100 g of this compound will contain.

So, if 100 g of this compound contain 14.33 g of hydrogen, it follows that the mass percent of hydrogen is 14.3%

4 0

4 years ago

Read 2 more answers

For the following pair, indicate which element has the lower first ionization energy: Match the words in the left column to the

emmainna [20.7K]

Answer:

For 1: The correct answer is Ge.

For 2: The correct answer is Te.

For 3: The correct answer is Ba.

For 4: The correct answer is Ag.

Explanation:

Ionization energy is defined as the energy required to remove an electron from the outermost shell of an isolated gaseous atom. It is represented as $E_i$

$X(g)\rightarrow X^+(g)+1e^-;E_i$

Ionization energy increases as we move from left to right in a period. This happens because the atomic radius of an element decreases moving across a period, which increases the effective attraction between the negatively charged electrons and positively-charged nucleus. Hence, the removal of electron from the outermost shell becomes difficult and requires more energy.

Ionization energy decreases on moving from top to bottom in a group. This happens because the number of shells increases as we move down the group. The electrons get added in the new shell. So, the shielding of outermost electrons from the inner ones is more which decreases the attraction between the electrons and the nucleus. Hence, the removal of electron from the outermost shell becomes easy and requires less energy.

For the given options:

Option 1:

Chlorine is the 17th element of the periodic table belonging to Period 3 and Group 17.

Germanium is the 32nd element of the periodic table belonging to Period 4 and Group 14.

Hence, germanium will have smaller first ionization energy.

Option 2:

Tellurium is the 52nd element of the periodic table belonging to Period 5 and Group 16.

Selenium is the 34th element of the periodic table belonging to Period 4 and Group 16.

Hence, tellurium will have smaller first ionization energy.

Option 3:

Barium is the 56th element of the periodic table belonging to Period 6 and Group 2.

Titanium is the 22nd element of the periodic table belonging to Period 4 and Group 4.

Hence, barium will have smaller first ionization energy.

Option 4:

Copper is the 29th element of the periodic table belonging to Period 4 and Group 11.

Silver is the 47th element of the periodic table belonging to Period 5 and Group 11.

Hence, silver will have smaller first ionization energy.

5 0

3 years ago

What is one issue that managers did not face 50 years ago?

Amiraneli [1.4K]

I think it’s D but don’t come at me if it’s wrong

5 0

3 years ago