1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² what elemts is it

What did you observe when heat was added to the penny with iodine?

Andru [333]

This is a difficult task because zinc is much more active than copper and could hardly be passivated. ... The sur- face immediately turns white (the color of copper(I) iodide) and the yellow-brown color of iodine quickly fades. Rinse the coin with water, brighten it with polish and cloth and begin the whole process again.N

8 0

3 years ago

A solution is made by dissolving 4.87 g of potassium nitrate in water to a final volume of 86.4 mL solution. What is the weight/

lara31 [8.8K]

Answer:

A solution is made by dissolving 4.87 g of potassium nitrate in water to a final volume of 86.4 mL solution. The weight/weight % or percent by mass of the solute is :

2.67%

Explanation:

Note : Look at the density of potassium nitrate in water if given in the question.

You are calculating weight /Volume not weight/weight % or percent by mass of the solute

Here the weight/weight % or percent by mass of the solute is asked : So first convert the VOLUME OF SOLUTION into MASS

Density of potassium nitrate in water KNO3 = 2.11 g/mL

$density=\frac{mass}{volume}$

Density = 2.11 g/mL

Volume of solution = 86.4 mL

$2.11=\frac{mass}{86.4}$

$mass = 2.11\times 86.4$

$mass=182.3grams$

Mass of Solute = 4.87 g

Mass of Solution = 183.2 g

w/w% of the solute =

$= \frac{mass\ of\ solute}{mass\ of\ solution}\times 100$

$=\frac{4.87}{183.2}\times 100$

w/w%=2.67%

8 0

3 years ago

1. Intermolecular forces do not have any effect on determining the physical properties of substances such as surface tension and

Scilla [17]

Answer:

1)false

2) false

3)True

4)True

5) false

6)false

7) true

8) d

9)false

10) b

5 0

3 years ago

Important substances found in food, which promote growth and good health

Rzqust [24]

Protein would be the main one.

6 0

3 years ago

Read 2 more answers

How many liters of air must react with 2500 mL of hexane in order for combustion to occur completely. The percentage of oxygen i

bagirrra123 [75]

Answer:

118750 ml

Explanation:

The chemical equation for complete combustion of hexane is given as;

2C6H14 + 19O2 → 12CO2 + 14H2O

From the equation of the reaction;

2 mol of C6H14 reacts with 19 mol of O2

2 ml of C6H14 reacts with 19 ml of O2

2500 mL of C6H14 would react with x ml of O2

2 = 19

2500 = x

x = 2500 * 19 / 2 = 23750 ml

Since oxygen is 20% of air;

23750 = 20 / 100 * (Volume of air)

Volume of air = 23750 * 100 / 20 = 118750 ml

7 0

3 years ago