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3 years ago

Please look at the picture attached. If you understand it, it would be nice because I have a Science quiz tomorrow!

Chemistry

1 answer:

ser-zykov [4K]3 years ago

8 0

Answer:

1. East on the box they are facing, West on the side from behind, North on the left side, South on the right side.

2. Because they all were facing towards the sun and the sun rise from east.

3. This one's answer is in the first answer.

4. The picture shows early morning because the shadow of the boys are in a flat position but if would have been late morning then it would not been covering that much area.

You might be interested in

What is the concentration of a solution with a volume of 1.38 mL that contains 17.36

Elden [556K]

Answer:

C = 107.97 mol/L

Explanation:

Given data:

Volume of solution = 1.38 mL (1.38 mL× 1 L /1000 mL = 0.00138 L)

Mass of ammonium sulfite = 17.36 g

Concentration of solution =?

Solution:

We will calculate the number of moles of ammonium sulfite.

Number of moles = mass/molar mass

Number of moles = 17.36 g / 116.15 g/mol

Number of moles = 0.149 mol

Concentration:

C = n/V

C = concentration

n = number of moles of solute

v = volume in L

C = 0.149 mol / 0.00138 L

C = 107.97 mol/L

5 0

3 years ago

You have an atom represented by X (not real by the way). X has 2 valence electrons. You have another atom Y that has 5 valence e

BabaBlast [244]

The chemical formula : X₃Y₂

<h3>Further explanation </h3>

The noble gas element is a stable class of elements. The noble gas element is monatomic. Stability of noble gases is caused by an electron configuration that has a stable configuration of 8 (has 8 valence electrons) except He with a duplet configuration (has 2 valence electrons)

Other elements that do not yet have electron configurations such as noble gases will try to achieve their stability by forming bonds between elements.

This is generally called the octet rule

X has 2 valence electrons.to achieve stability, element X will release 2 electrons to form X²⁺

Y has 5 valence electrons, to achieve stability, the element Y will attract/ add electrons to form Y³⁻

The two compounds will form a compound with the charges crossed : X₃Y₂

6 0

4 years ago

What are the coefficients that will balance the skeleton equation below?

Vesna [10]

Answer:

the answer is 1,3,2

Explanation:

Balance equation

5 0

3 years ago

1.00 M CaCl2 Density = 1.07 g/mL

Lesechka [4]

Explanation:

Molarity of solution = 1.00 M = 1.00 mol/L

In 1 L of solution 1.00 moles of calcium chloride is present.

Mass of solute or calcium chloride = m

$m = 1 mol\times 111 g/mol = 111 g$

Mass of solution = M

Volume of solution = V = 1L = 1000 mL

Density of solution , d= 1.07 g/mL

$M=d\times V=1.07 g/mL\times 1000 mL=1,070 g$

1) The value of %(m/M):

$\frac{m}{M}\times 100=\frac{111 g}{1,070 g}\times 100=10.37\%$

2) The value of %(m/V):

$\frac{m}{V}\times 100=\frac{111 g}{1000 L}\times 100=11.1\%$

$Molality = \frac{\text{Moles of compound }}{\text{mass of solvent in kg}}$

$Normality=\frac{\text{Moles of compound }}{n\times \text{volume of solution in L}}$

n = Equivalent mass

n = $\frac{\text{molar mass of ion}}{\text{charge on an ion}}$

3) Normality of calcium ions:

Moles of calcium ion = 1 mol (1 $CaCl_2$ mole has 1 mole of calcium ion)

$n=\frac{40 g/mol}{2}=20$

$=\frac{1 mol}{20 g/mol\times 1L}=0.050 N$

4) Normality of chlorine ions:

Moles of chlorine ion = 2 mol (1 $CaCl_2$ mole has 2 mole of chlorine ion)

$n=\frac{35.5 g/mol}{1}=35.5$

$=\frac{2 mol}{35.5 g/mol\times 1L}=0.056 N$

Moles of calcium chloride = 1.00 mol

Mass of solvent = Mass of solution - mass of solute

= 1,070 g - 111 g = 959 g = 0.959 kg ( 1 g =0.001 kg)

5) Molality of the solution :

$\frac{1 mol}{0.959 kg}=1.043 mol/kg$

Moles of calcium chloride = $n_1=1mol$

Mass of solvent = 959 g

Moles of water = $n_2=\frac{959 g}{18 g/mol}=53.28 mol$

Mass of solvent = 959 g

6) Mole fraction of calcium chloride =

$\chi_1=\frac{n_1}{n_1+n_2}=\frac{1mol}{1 mol+53.28 mol}=0.01842$

7) Mole fraction of water =

$\chi_2=\frac{n_2}{n_1+n_2}=\frac{53.28 mol}{1mol+53.28 mol}=0.9816$

8) Mass of solution = m'

Volume of the solution= v = 100 mL

Density of solution = d = 1.07 g/mL

$m'=d\times v=1.07 g/ml\times 100 g= 107 g$

Mass of 100 mL of this solution 107 grams of solution.

9) Volume of solution = V = 100 mL

Mass of solution = M'' = 107 g

Mass of solute = m

The value of %(m/V) of solution = 11.1%

$11.1\%=\frac{m}{100 mL}\times 100$

m = 11.1 g

Mass of solvent = M''- m = 107 g -11.1 g = 95.9 g

95.9 grams of water was present in 100 mL of given solution.

3 0

3 years ago

How many moles are in a sample of 1.52 x 1024 atoms of mercury (Hg)?

OLEGan [10]

The answer is:

2.5 moles

The explanation:

when avogadro's number = 6.02 * 10^23

and when 1 mole of the sample will give → 6.02*10^23 atoms

So, ??? mole of the sample will give→ 1.52 x 10^24 atoms

∴ number of moles = (1.52 X 10^24) * 1 mole / (6.02X10^23)

= 2.5 moles

8 0

3 years ago