please help me with questions 3, 4 & 5:)

Answer:

these species share a common ancestor

Explanation:

Answer:

4) C

6) true

I am not sure about 5th one

4) evaporation rate  

5) acetone

6) true

Answer:

40.0L is the volume the CO occupy

Explanation:

To solve this question we must assume the gas is at STP. To find the volume of a gas using the moles, temperature and pressure of the gas we have to use:

PV = nRT

V = nRT / P

Where V is volume in liters

n are moles of the gas -Molar mass CO: 28g/mol-

50.0g * (1mol / 28g) = 1.786 moles CO

R is gas constant = 0.082atmL/molK

T is absolute temperature = 273.15K at STP

P is pressure = 1atm at STP

Replacing:

V = 1.786moles*0.082atmL/molK*273.15K / 1atm

V = 40.0L is the volume the CO occupy

Answer:

The interior of the Earth, like that of the other terrestrial planets, is chemically divided into layers. The Earth has an outer silicate solid crust, a highly viscous mantle, a liquid outer core that is much less viscous than the mantle, and a solid inner core.

Answer:

Kinetic

Explanation:

Answer:

the answer is d. 74.02

Explanation:

When ogyen all together with the different things to get this.

Answer:

mole is equal to 1 moles Potassium Chloride, or 74.5513 grams.

Answer:

The answer is 7.7 ×10¹⁰

Explanation:

7.0 × 10³ × 1.1 × 10⁷

7.7 ×10¹⁰

Thus, The answer is 7.7 ×10¹⁰

-TheUnknownScientist

Answer:

subscript is a character

Explanation:

A subscript is a character (such as a number or letter) that is set slightly below or above the normal line of type, respectively. It is usually smaller than the rest of the text.

Answer:0.87

Explanation:

Answer:

B. In a wet, hilly area

Explanation:

We know that for a landslide to happen, there has to be a down hill slope so it can fall.

This eliminates answers C, D and E.

So we are left with A and B

Now we can look at this in a real life scenario. If you have ever walking on wet ground, you will know that is weaker than dry ground. Knowing this, we know the answer will have to be answer B.

Answer: The compound formed between nitrogen (N) and nitrogen (N) a polar covalent bond because there is less than a 0.4 difference in electronegativity between the atoms.

Explanation:

If electronegativity difference between two atoms is less than 0.4 then bond formed is a pure covalent bond.

If electronegativity difference between two atoms is between 0.4 to 1.8 then bond formed is a polar covalent bond.

If electronegativity difference between two atoms is greater than 1.8 then bond formed is an ionic bond.

The electronegativity value of a nitrogen atom is 3.04. Hence, the electronegativity difference of [tex]N_{2}[/tex] molecule is as follows.

[tex]Electronegativity difference = electronegativity value of N - electronegativity value of N\\= 3.04 - 3.04\\= 0[/tex]As the electronegativity difference is 0 which is less than 0.4.

Hence, we can conclude that the compound formed between nitrogen (N) and nitrogen (N) a polar covalent bond because there is less than a 0.4 difference in electronegativity between the atoms.

Answer:

The first one is balanced. The second one is not.

Explanation:

The first one is balanced because there are the same amount of elements on the reactant side as there are on the product side. The second one is not balanced because there are not the same amount of elements on the reactant side as there are on the product side. Therefore, it is not balanced

More Detailed: first example

Reactant side (left of arrow)

H: 2

C: 1

O: 3

Product side (right of arrow)

H: 2

C: 1

O: 3

More detailed: second example

Reactant side:

Na: 1

O: 1

H: 1

C: 1

Product side:

Na: 2

O: 4

H: 2

C: 1

the variables needed to balance this equation is 2,1, 1, 1.

Answer:

ok

Explanation:

Answer:

Is C

Explanation:

Explanation:

Hi,

The number of protons is equal to the atomic number. The number of electrons in a neutral atom is equal to the number of protons. So, in this case, you have 72 protons and 72 electrons.

I hope this helps :)

If an element has the atomic number 72, then the number of protons is also equal to 72. As it is clearly mentioned in the question that it is a neutral atom, which means the number of protons is equal to the number of electrons which is also 72.

An atomic number may be defined as the number of a chemical element in the modern periodic table through which the elements are systematically arranged in order of increasing the number of protons in the nucleus.

According to the context of this question, the atomic number of every element is always equal to the number of protons it has. While in a neutral atom, the number of electrons is equal to the number of protons. For calculating the number of neutrons, you have to subtract the atomic number from the atomic mass.

Therefore, there are 72 protons of an element whose atomic number is 72. The number of electrons is also 72.

To learn more about Atomic numbers, refer to the link:

https://brainly.com/question/27655686

#SPJ2

Answer:

What is that supose to mean?

Answer:

I would never think that would be even a real question....what does it mean? what math problem is this?! I've never seen this in my life...does it mean... CCHHCHCH? *laughs nervously*

Explanation:

Have a Blessed Day.

Answer:

18.368 Liters

Explanation:

Given that balanced Acetone oxidation,

= C3H6O + 4O2 = 3CO2 + 3H2O

lets assume volume of acetone = 1 liter

mass of acetone =  50 mg

number of moles present = (5*10^-3)g / ( 58.08 ) = 0.0000861 mol

Given that : I mol of ( acetone ) = 4 mol of oxygen

∴0.0000861 mol of acetone = 0.0003444 mol of oxygen

also note that the ratio of air to oxygen is

0.21 mol of oxygen  = 1 mol of air

∴ 0.0003444 mol of oxygen  =  0.00164 mol of air      (0.0003444 / 0.21 )

note : 1 mol at STP = 22.4 L     (at STP = Temperature = O°C

Finally the theoretically oxygen demand in liters of air for a 50 mg/L of acetone to decompose

Given that Acetone decompose/degrade completely between 500°C - 600°

we will take 500°  for the sake of this calculation

The oxygen demand in liters will be

=  22.4 * 0.00164 * 500 = 18.368 Liters

The theoretical oxygen demand in liters of air for a 50 mg / L acetone solution, to decompose completely is 18.368 Liters.

Moles of any substance will be calculated as:

n = W/M, where

W = given mass

M = molar mass

Given chemical reaction is:

CH₃COCH₃ + 4O₂ → 3CO₂ + 3H₂O

Given mass of acetone = 50mg = 0.05g

Moles of acetone = 0.05g / 58.08g/mol = 0.0000861 mole

From the stoichiometry of the reaction, it is clear that:

1 mole of CH₃COCH₃ = 4 moles of O₂

0.0000861 mole of CH₃COCH₃ = 4×0.0000861=0.0003444 moles of O₂

We know that ratio of air is:

0.21 mole of oxygen present = in 1 mole of air

0.0003444 mole of oxygen present = in 0.0003444/0.21=0.00164 mole of air

At STP 1 mole of gas is present in 22.4 Liter.

Degradation of acetone takes place in 500°C - 600°C.

Theoretical oxygen demand = 22.4×0.00164×500 = 18.368 Liters

Hence, theoretical oxygen demand is 18.368 Liters.

To know more about theoretical oxygen demand, visit the below link:

https://brainly.com/question/13251445

Answer:

V=d/t

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Answer:

I think the answer is b

Explanation:

I hope this helps

Answer:

The molecular formula for a compound can be the same as or a multiple of the compound's empirical formula. Molecular formulas are compact and easy to communicate; however, they lack the information about bonding and atomic arrangement that is provided in a structural formula.

Explanation:

Answer: Hello Luv......

Hope this helps. Please mark me brainest... Anna ♥

Explanation:

The molecular formula for a compound can be the same as or a multiple of the compound's empirical formula. Molecular formulas are compact and easy to communicate; however, they lack the information about bonding and atomic arrangement that is provided in a structural formula.

Answer:

13.25 M

Explanation:

Molarity is moles over liters so simply plug your values in as such:

5.30 mol ÷ 0.400 L = 13.25 M

H3PO4 + Ba(OH)2 --> Ba3(PO4)2 + H2O

so, (A) H2O + Ba3(PO4)2 is your answer.

Answer:

Explanation:

A 12.48 g sample of an unknown metal, heated to 99.0 °C was then plunged into 50.0 mL of 25.0 °C water. The temperature of the water rose to 28.1 Go to calculating final temperature when mixing two samples of water ... Problem #1: A 610. g piece of copper tubing is heated to 95.3 °C and placed in an ... The two rings are heated to 65.4 °C and dropped into 12.4 mL of water at 22.3 °C. ... Problem #4: A 5.00 g sample of aluminum (specific heat capacity = 0.89 J g¯1

Answer:

His name is Harold

Explanation:

Answer:

Zinc oxide is  used in the manufacture of  many products such as paints, rubber, cosmetics, pharmaceuticals, plastics, inks, soaps, batteries, textiles and electrical equipment.

Explanation:

Answer:

1. direct current. 2. electrical power

Explanation

i believe number 2 is right

Answer:

0.2 cm

Explanation:

looking at the ruler, you can see that the diameter is 0.4 cm. to get the radius, just divide by two, which gets 0.2 cm as the radius

Answer:

164.088 g/mol

Explanation: hope this helps

Answer:

Calcium nitrate

Explanation:

164.088 g/mol

give me the brainliest plss