The colour imparted to a flame by calcium ion?

What is the molarity of an aqueous solution that contains 78g of C6H12O6 dissolved in 2500 mL of solution?

dusya [7]

Answer:

$\boxed {\boxed {\sf molarity = 0.17 \ M \ C_6H_12O_6}}$

Explanation:

Molarity is found by dividing the moles of solute by liters of solution.

$molarity = \frac {moles}{liters}$

We are given grams of a compound and milliliters of solution, so we must make 2 conversions.

1. Gram to Moles

We must use the molar mass. First, use the Periodic Table to find the molar masses of the individual elements.

C: 12.011 g/mol
H: 1.008 g/mol
O: 15.999 g/mol

Next, look at the formula and note the subscripts. This tells us the number of atoms in 1 molecule. We multiply the molar mass of each element by its subscript.

6(12.011)+12(1.008)+6(15.999)=180.156 g/mol

Use this number as a ratio.

$\frac {180.156 \ g\ C_6H_12 O_6}{ 1 \ mol \ C_6H_12O_6}$

Multiply by the given number of grams.

$78 \ g \ C_6H_12O_6 *\frac {180.156 \ g\ C_6H_12 O_6}{ 1 \ mol \ C_6H_12O_6}$

Flip the fraction and divide.

$78 \ g \ C_6H_12O_6 *\frac { 1 \ mol \ C_6H_12O_6}{180.156 \ g\ C_6H_12 O_6}$

$\frac { 78 \ mol \ C_6H_12O_6}{180.156 }= 0.432958102977 \ mol \ C_6H_12O_6$

2. Milliliters to Liters

There are 1000 milliliters in 1 liter.

$\frac {1 \ L }{ 1000 \ mL}$

Multiply by 2500 mL.

$2500 \ mL* \frac {1 \ L }{ 1000 \ mL}$

$2500 * \frac {1 \ L }{ 1000 }= 2.5 \ L$

3. Calculate Molarity

Finally, divide the moles by the liters.

$molarity = \frac {0.432958102977 \ mol \ C_6H_12O_6}{ 2.5 \ L}$

$molarity = 0.173183241191 \ mol \ C_6H_12O_6/L$

The original measurement has 2 significant figures, so our answer must have the same. That is the hundredth place and the 3 tells us to leave the 7.

$molarity \approx 0.17 \ mol \ C_6H_12O_6 /L$

1 mole per liter is also equal to 1 M.

$molarity = 0.17 \ M \ C_6H_12O_6$

3 0

3 years ago

For each of the following compounds, state whether it is ionic or covalent, and if it is ionic, write the symbols for the ions i

kupik [55]

Answer :

Covalent compound : It is defined as the compound which is formed by the sharing of electrons between the atoms forming a compound.

The covalent compound are usually formed when two non-metals react.

Ionic compound : It is defined as the compound which is formed when electron gets transferred from one atom to another atom.

All the polyatomic ions always form an ionic compound.

Polyatomic ions : It is a charged species that composed of two or more atoms and these charged species are bonded by the covalent bond.

For the given options:

Option A: $KClO_4$

This compound is formed by the combination of potassium, $K^+$ which is a metal and $ClO_4^-$ ion which is a polyatomic ion. Thus, it will form an ionic compound.

Option B: $Mg(C_2H_3O_2)_2$

This compound is formed by the combination of magnesium, $Mg^{2+}$ which is a metal and $C_2H_3O_2^{-}$ ion which is a polyatomic ion. Thus, it will form an ionic compound.

Option C: $H_2S$

Hydrogen and sulfur, both are non-metals and they will form a covalent compound.

Option D: $Ag_2S$

This compound is formed by the combination of silver, $Ag^{+}$ which is a metal and sulfur, $S^{2-}$ which is a non-metal. Thus, it will form an ionic compound.

Option E: $N_2Cl_4$

Nitrogen and chlorine, both are non-metals and they will form a covalent compound.

Option F: $Co(NO_3)_2$

This compound is formed by the combination of cobalt, $Co^{2+}$ which is a metal and $NO_3^{-}$ ion which is a polyatomic ion. Thus, it will form an ionic compound.

6 0

3 years ago

Based on the enthalpy changes given for the reactions, which reactions are endothermic?

aksik [14]

Answer:

the first and last

Explanation:

the enthalpy Change is positive.

please like and Mark as brainliest

6 0

3 years ago

If your end product is 200.0 g KMnO4 how much KOH did you start with?

aniked [119]

Answer:

$m_{KOH}= 142.0gKOH$

Explanation:

Hello there!

In this case, according to the following chemical reaction we found on goo gle as it was not given:

$2MnO_2+4KOH+O_2\rightarrow 2KMnO4+2KOH+H_2$

Whereas we can see a 2:4 mole ratio of potassium permanganate product to potassium hydroxide reactant with molar masses of 158.03 g/mol and 54.11 g/mol respectively. In such a way, by developing the following stoichiometric setup, we obtain the mass of KOH to start with:

$m_{KOH}=200.0gKMnO_4*\frac{1molKMnO_4}{158.03gKMnO_4}*\frac{4molKOH}{2molKMnO_4} *\frac{56.11gKOH}{1molKOH}\\\\m_{KOH}= 142.0gKOH$

Best regards!

8 0

3 years ago

A student prepares a mixture of sugar and coffee. The sugar seems to disappear as it mixes with the coffee.

butalik [34]

Answer:homogeneous

Explanation:

4 0

4 years ago

Read 2 more answers