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3 years ago

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Chemistry

1 answer:

Scilla [17]3 years ago

4 0

Answer: 1. C. polar covalent: electrons shared between silicon and sulfur but attracted more to the sulfur

2. B) $NH_3$

3. B) Fluorine

Explanation:

1. A polar covalent bond is defined as the bond which is formed when there is a difference of electronegativities between the atoms.

Electronegativity difference = electronegativity of sulphur- electronegativity of silicon = 2.5 -1.8 = 0.7

Thus as electronegativity difference is less than 1.7 , the cond is polar covalent and as electronegativity of sulphur is more , the electrons will be more towards sulphur.

2. A molecular compound is usually composed of two or more nonmetal elements. Example: $NH_3$

Ionic compound is formed by the transfer of electrons from metals to non metals. Example: $Mg_3N_2$ , $AlCl_3$ and $LiBr$

3. For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.

Here K is having an oxidation state of +1 and as the compound formed is KZ, the oxidation state of non metallic element Z should be -1. Thus the element Z is flourine which exists as diatomic gas $F_2$

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5.22*10^-3 = ?*10^-2

Andrew [12]

x=0.522 is the answer

x times :10^-2=5.22 times 10^{-3}\

simplify 10^-3: 5.22/1000= x times 10^-2 = 5.22/1000

simplify 10^-2 1/100 = x 1/100=5.22/1000

Multiply both sides by 100 100x 1/100 = 5.22x100/1000

simplify 0.522 sorry I took so long I did the best i could to explain it

Hope this helps!

6 0

3 years ago

What is the energy required to change a spherical drop of water to five smaller spherical drops of equal size? At room temperatu

pav-90 [236]

This is a straightforward question related to the surface energy of the droplet. 

You know the surface area of a sphere is 4π r² and its volume is (4/3) π r³. 

With a diameter of 1.4 mm you have an original droplet with a radius of 0.7 mm so the surface area is roughly 6.16 mm² (0.00000616 m²) and the volume is roughly 1.438 mm³. 

The total surface energy of the original droplet is 0.00000616 * 72 ~ 0.00044 mJ 

The five smaller droplets need to have the same volume as the original. Therefore 

5 V = 1.438 mm³ so the volume of one of the smaller spheres is 1.438/5 = 0.287 mm³. 

Since this smaller volume still has the volume (4/3) π r³ then r = cube_root(0.287/(4/3) π) = cube_root(4.39) = 0.4 mm. 

Each of the smaller droplets has a surface area of 4π r² = 2 mm² or 0.0000002 m². 

The surface energy of the 5 smaller droplets is then 5 * 0.000002 * 72.0 = 0.00072 mJ 
From this radius the surface energy of all smaller droplets is 0.00072 and the difference in energy is 0.00072- 0.00044 mJ = 0.00028 mJ. 

Therefore you need roughly 0.00028 mJ or 0.28 µJ of energy to change a spherical droplet of water of diameter 1.4 mm into 5 identical smaller droplets.

3 0

3 years ago

Gaseous ethane reacts with gaseous oxygen gas to produce gaseous carbon dioxide and gaseous water . What is the theoretical yiel

Effectus [21]

Answer:

1) Write the balanced equation:

2C2H6 + 7O2 ---> 4CO2 + 6H2O

2) Determine limiting reagent:

C2H6 ⇒ 13.8 g / 30.0694 g/mol = 0.45894 mol

O2 ⇒ 45.8 g / 31.9988 g/mol = 1.4313 mol

C2H6 ⇒ 0.45894 / 2 = 0.22947

O2 ⇒ 1.4313 / 7 = 0.20447

Oxygen is limiting.

3) Determine theoretical yield of water:

The oxygen : water molar ratio is 7 : 6

7 is to 6 as 1.4313 mol is to x

x = 1.2268286 mol of water

4) Convert moles of water to grams:

1.2268286 mol times 18.015 g/mol = 22.1 g (to three sig figs)

Solution to (b):

14.2 g / 22.1 g = 64.2%

Explanation:

8 0

3 years ago

1 What is the pH of a substance that has a hydrogen ion concentration of 1.2 x10-2 M2 ZpG

Andrej [43]

Answer:

The pH o.s the s.u.b.st.a.n.c.e is 1,92.

Explanation:

pH = -log (H +)= -l.o.g (1.2 x 10^-2 )=1,92

hope this helps

plz mark brainliest

4 0

2 years ago

Read 2 more answers

What is the pressure of a gas in torr if its pressure is 305 kPa?

FromTheMoon [43]

Answer:

the pressure of the gas in torr is 2280 torr

Explanation:

The pressure of a gas in torr can be calculated by converting its pressure in kPa to atmospheres and then converting the atmospheric pressure to torr.

One atmosphere is equal to 101.325 kPa. Therefore, the pressure of the gas in atmospheres is 305 kPa / 101.325 kPa/atm = 3.00 atm.

One torr is equal to 1/760 of an atmosphere. Therefore, the pressure of the gas in torr is 3.00 atm * 760 torr/atm = 2280 torr.

Therefore, the pressure of the gas in torr is 2280 torr

3 0

2 years ago