Chemistry College

## Answers

**Answer 1**

**Answer:**

296 g BaBr₂

**General Formulas and Concepts:**

**Math**

Pre-Algebra

Order of Operations: **BPEMDAS**

BracketsParenthesisExponentsMultiplicationDivisionAdditionSubtractionLeft to Right

**Chemistry**

Atomic Structure

Reading a Periodic TableMolesAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

Stoichiometry

Using Dimensional Analysis**Explanation:**

Step 1: Define

[Given] 8.56 × 10²³ formula units BaBr₂

[Solve] grams BaBr₂

Step 2: Identify Conversions

Avogadro's Number

[PT] Molar Mass of Ba - 137.33 g/mol

[PT] Molar Mass of Br - 35.45 g/mol

Molar Mass of BaBr₂ - 137.33 + 2(35.45) = 208.23 g/mol

Step 3: Convert

[DA} Set up: [tex]\displaystyle 8.56 \cdot 10^{23} \ formula \ units \ BaBr_2(\frac{1 \ mol \ BaBr_2}{6.022 \cdot 10^{23} \ formula \ units \ BaBr_2})(\frac{208.23 \ g \ BaBr_2}{1 \ mol \ BaBr_2})[/tex][DA] Multiply/Divide [Cancel out units]: [tex]\displaystyle 295.99 \ g \ BaBr_2[/tex]

Step 4: Check

*Follow sig fig rules and round. We are given 3 sig figs.*

295.99 g BaBr₂ ≈ 296 g BaBr₂

Thank you agenthammerx for helping me with this question!

**Answer 2**

**Answer:**

**296 g BaBr₂**

**General Formulas and Concepts:**

**Math**

**Pre-Algebra**

**Order of Operations: BPEMDAS**

**Brackets**

**Parenthesis**

**Exponents**

**Multiplication**

**Division**

**Addition**

**Subtraction**

**Left to Right**

**Chemistry**

**Atomic Structure**

**Reading a Periodic Table**

**Moles**

**Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.**

**Stoichiometry**

**Using Dimensional Analysis**

**Explanation:**

**Step 1: Define**

**[Given] 8.56 × 10²³ formula units BaBr₂**

**[Solve] grams BaBr₂**

**Step 2: Identify Conversions**

**Avogadro's Number**

**[PT] Molar Mass of Ba - 137.33 g/mol**

**[PT] Molar Mass of Br - 35.45 g/mol**

**Molar Mass of BaBr₂ - 137.33 + 2(35.45) = 208.23 g/mol**

**Step 3: Convert**

**[DA} Set up: **

**[DA] Multiply/Divide [Cancel out units]: **

**Step 4: Check**

**Follow sig fig rules and round. We are given 3 sig figs.**

**295.99 g BaBr₂ ≈ 296 g BaBr₂**

## Related Questions

milk milk milk........

### Answers

**Answer:**

gimme that chocky milk.....

**Explanation:**

**Answer:**

m i l k

**Explanation:**

A 50.0-mL volume of 0.15 M HBr is titrated with 0.25 M KOH. Calculate the pH after the addition of 13.0 mL of KOH. Express your answer numerically.

### Answers

**Answer:**

pH= 1.17

**Explanation:**

The neutralization reaction between HBr (acid) and KOH (base) is given by the following equation:

HBr(aq) + KOH(aq) → KBr(aq) + H₂O(l)

According to this equation, 1 mol of HBr reacts with 1 mol of KOH. Then, the moles can be expressed as the product between the molarity of the acid/base solution (M) and the volume in liters (V). So, we calculate the moles of acid and base:

Acid:

M(HBr) = 0.15 M = 0.15 mol/L

V(HBr) = 50.0 mL x 1 L/1000 mL = 0.05 L

moles of HBr = M(HBr) x V(HBr) = 0.15 mol/L x 0.05 L = 7.5 x 10⁻³ moles HBr

Base:

M(KOH) = 0.25 M = 0.25 mol/L

V(HBr) = 13.0 mL x 1 L/1000 mL = 0.013 L

moles of HBr = M(HBr) x V(HBr) = 0.25 mol/L x 0.013 L = 3.25 x 10⁻³ moles KOH

Now, we have: 7.5 x 10⁻³ moles HBr > 3.25 x 10⁻³ moles KOH

HBr is a strong acid and KOH is a strong base, so they are completely dissociated in water: the acid produces H⁺ ions and the base produces OH⁻ ions. So, the difference between the moles of HBr and the moles of KOH is equal to the moles of remaining H⁺ ions after neutralization:

moles of H⁺ = 7.5 x 10⁻³ moles HBr - 3.25 x 10⁻³ moles KOH = **4.25 x 10⁻³ moles H⁺**

From the definition of pH:

pH = -log [H⁺]

The concentration of H⁺ ions is calculated from the moles of H⁺ divided into the total volume:

total volume = V(HBr) + V(KOH) = 0.05 L + 0.013 L = 0.063 L

[H⁺] = (moles of H⁺)/(total volume) = 4.25 x 10⁻³ moles/0.063 L = 0.067 M

Finally, we calculate the pH after neutralization:

pH = -log [H⁺] = -log (0.067) = **1.17 **

Please help me with my homework thanks

### Answers

Answer:

electrons are transferred from the clouds to the grounf

Explanation:

**Answer:**

the answer is circle 3 hope it helps

what is the answer please

### Answers

**Answer:**

A.

**Explanation:**

A decomposition reaction is when one reactant (the substances to the left of the arrow in the reaction) breaks apart into two or more products (the substances to the right of the arrow).

Because KClO3 is breaking down into KCl and O2, it's a decomposition reaction.

Hydrogen has an oxidation number of +1 in all compounds excepts when it binds with metals and has an oxidation state of -1.

### Answers

**Answer:**

See explanation

**Explanation:**

In the periodic table, hydrogen is placed in group 1 for convenience. Hydrogen is not a metal, however, its common oxidation state is +1. It easily forms a univalent positive ion just like group 1 elements.

So, when hydrogen is combined with strongly electropositive metals such as sodium, lithium, etc, hydrogen accepts one electron and exhibits an oxidation state of -1 in those compounds.

Such compounds in which hydrogen is combined with strongly electropositive metals to give a binary compound is called a hydride.

Help help help !!!!!!

### Answers

Answer:

3. 116.5 V

4. 119.6 V

Explanation:

3. Determination of the voltage.

Resistance (R) = 25 Ω

Current (I) = 4.66 A

Voltage (V) =?

V = IR

V = 4.66 × 25

V = 116.5 V

Thus, the voltage is 116.5 V

4. Determination of the voltage.

Current (I) = 9.80 A

Resistance (R) = 12.2 Ω

Voltage (V) =?

V = IR

V = 9.80 × 12.2

V = 119.6 V

Thus, the voltage is 119.6 V

Which postmortem parameter is fixed by 8 hours?

1)cloudiness of the eyes

2)rigor mortis

3)livor mortis

4)putrefaction

### Answers

The postmortem cooling or algor mortis gets fixed by 8- 10 hours after death. The temperature of the body after death can be used to determine the time since death.

A student mixes 5.00 mL of 0.0020 M Fe(NO3)3 with 3.00 mL of 0.0020 M KSCN solution and 2.00 mL water at a certain temperature. He places a sample of the resulting solution in a spectrometer, and measures the transmittance as 23% at 447 nm. What are the initial concentrations of [Fe3 ] and [SCN-]

### Answers

**Answer:**

[Fe⁺³] = 0.0010 M

[SCN⁻] = 0.0006 M

**Explanation:**

First we calculate how many moles of Fe⁺³ and SCN⁻ were added, using *the given volumes and concentrations*:

Fe⁺³ ⇒ 5.00 mL * 0.0020 M = 0.010 mmol Fe⁺³SCN⁻ ⇒ 3.00 mL * 0.0020 M = 0.006 mmol SCN⁻

Now we can calculate the initial concentrations, after *calculating the new volume of the solution*:

New volume = 5.00 mL + 3.00 mL + 2.00 mL = 10.00 mL[Fe⁺³] = 0.010 mmol / 10.00 mL = 0.0010 M[SCN⁻] = 0.006 mmol / 10.00 mL = 0.0006 M

Scientists have been classifying living organisms for centuries. In the 1970s, organisms were classified in a five-kingdom

classification scheme. However, two decades later, organisms called Archaebacteria were discovered. This led to a three-domain

system of classification that combined some of the previous five-kingdom schemes.

What does this change in classification methods demonstrate?

### Answers

**Answer:**

Classification is important because it allows scientists to identify, group, and properly name organisms via a standardized system (Linnaeus Taxonomy); based on similarities found in the organisms DNA/RNA (genetics), Adaptations (Evolution), and Embryonic development (Embryology) to other known organisms to better.

**Hope I helped!!**

The **five kingdoms** of classifications were animalia, plant, fungi, protista and monera. Later **Archaebacteria** was discovered and this led to the 3 **kingdom classification** animalia, plantae and protista.

What is biological classification?

There are different** classifications **for living things based on their nature, body and origin. The **kingdom animalia** includes all the animals including human beings.

**Kingdom plante** includes all the plants and kingdom fungi, protista and monera are of microbes. Later the discovery and study of Archaebacteria proved that they exhibit similar body type and functions as bacterias.

After that, scientists turned into **3 kingdom classification**, where all the prokaryotic organisms including protists, monera and fungi classified as one. The **evolutional changes** originated in them made this classification.

To find more on **biological classification**, refer here:

https://brainly.com/question/2994982

#SPJ2

What BEST describes the relation of a new population to an increase in the amount of space it occupies? a - The population will die out

b - The population will remain constant

c - The population will grow exponentially

### Answers

answer c is correct

what type of energy is a furnace and using a telephone? pls help

### Answers

**Answer:**

hope this helped

**Explanation:**

Radiant energy is created through electromagnetic waves and was discovered in 1885 by Sir William Crookes. Fields in which this terminology is most often used are telecommunications, heating, radiometry, lighting, and in terms of energy created from the sun.

Answer:

radiation energy is created through electromagneic waves and was discovered in 1885 by Sir William Crookes

Explanation:

what is the structure of methane

### Answers

**Answer:**

CH4

**Explanation:**

if it is wrong, i blame my brain

A compound contains 0.5 mol Na, 0.5 mol N, and 10 mol H. The empirical formula of the

compound is -

### Answers

**Answer:**

NaNH₂₀

**Explanation:**

0.5 mol Na, 0.5 mol N, and 10 mol H

To obtain the empirical formulae, we find the mole ratio between the elements and this is done by dividing all through by the smallest mol (0.5)

Na = 0.5 / 0.5 = 1

N = 0.5 / 0.5 = 1

H = 10 / 0.5 = 20

The mole ratio is used to write the empirical formulae. It is given as;

NaNH₂₀

A force of 10 N pulls an object to the right, and a force of 7 N pulls to the left, what is the net force

### Answers

**Answer:**

2 N

**Explanation:**

How many grams of a 26.9% sugar solution contain 49.0 g of sugar?

### Answers

**Answer:**

182.156g

**Explanation:**

grams = 49/.269 = 182.156g needed

The smallest arteries in your body are called _____. arterioles capillaries veins bronchioles

### Answers

Answer: arterioles

Explanation:

Choose a reasonable explanation to account for the differences. There may be more than one possible reason that makes sense, just select one of them.

A. It is possible not all of the water was evaporated from the sand, causing the recovered mass to be higher.

B. It is possible not all of the water was evaporated from the sand, causing the recovered mass to be lower.

C. While drying the NaCl, the liquid boiled and some splattered out of the evaporating dish, causing the recovered mass to be lower

D. While drying the NaCl, the liquid boiled and some splattered out of the evaporating dish, causing the recovered mass to be higher.

E. There was no difference in recovered and original mass, so there is no difference to account for.

### Answers

**Answer:**

A. It is possible not all of the water was evaporated from the sand, causing the recovered mass to be higher

D. While drying the NaCl, the liquid boiled and some splattered out of the evaporating dish, causing the recovered mass to be higher.

**Explanation:**

Sand absorbs water and stores it. The sunlight causes the water to evaporate but sand can hold some of the water inside it. This results in increase in mass of the sand. The mass of sand before and after the water evaporation can be different.

Draw the structure formula for

1-ethyl-2,3-dimethylbenzene

Please help me

### Answers

**Answer:**

Please see the attached picture.

**Explanation:**

1) Draw a benzene ring

2) On the first carbon, add a CH₂CH₃ (known as ethyl) since its location number is 1.

3) 'Dimethyl' refers to 2 methyl (CH₃) branches. The location numbers are 2 and 3, thus add a CH₃ on the 2nd and 3rd carbons.

How many moles of KBr are present in 500 ml of a 0.8 M KBr solution?

1. 1.6

2. .4

3. .625

4. 625

5. .0016

### Answers

**Answer:**

2) 0.4 mol

**Explanation:**

**Step 1: Given data**

Volume of the solution (V): 500 mLMolar concentration of the solution (M): 0.8 M = 0.8 mol/L

**Step 2: Convert "V" to L**

We will use the conversion factor 1 L = 1000 mL.

500 mL × 1 L/1000 mL = 0.500 L

**Step 3: Calculate the moles of KBr (solute)**

The molarity is the quotient between the moles of solute (n) and the liters of solution.

M = n/V

n = M × V

n = 0.8 mol/L × 0.500 L = 0.4 mol

Use the solubility rules from the Lab 4 introduction and your knowledge of qualitative separation schemes from the lab to answer the following questions. The qualitative analysis experiment you did is actually an abbreviated version of a much larger analysis scheme in which many different cations are separated and identified. Suppose a mixture contains Ag , K , NH4 , Hg22 , Pb2 , Mg2 , Sr2 , Ba2 , Cu2 , Al3 and Fe3 .

(a) Which of the following ions could you separate, by causing them to precipitate, with the addition of HCl?

Ag+ K+ NH4+

Hg22+ Pb2+ Mg2+

Sr2+ Ba2+ Cu2+

Al3+ Fe3+

(b) After the addition of HCl, the above sample is centrifuged and decanted. Which of the following cations remaining in the supernatant could you separate, by causing them to precipitate, with the addition of H2SO4? (Hint: H2SO4 is a source of sulfate ions. Select all that apply.)

Ag+ K+ NH4+

Hg22+ Pb2+ Mg2+

Sr2+ Ba2+ Cu2+

Al3+ Fe3+

### Answers

**Answer:**

a13+a13

**Explanation:**

A cell biologist measures the volume of a bacteria cell. The volume is 6.027x10-10 L. What is the volume in picoliters? Write your answer as a decimal.

pL

### Answers

**Answer:**

Volume of bacteria cell into Pico liters = 60.27 Pico liters

**Explanation:**

**Given:**

Volume of bacteria cell = 6.027 x 10⁻¹⁰ L

**Find:**

Volume of bacteria cell into Pico liters

**Computation:**

1 L = 10¹² Pico liters

So,

Volume of bacteria cell = 6.027 x 10⁻¹⁰ L

Volume of bacteria cell = 6.027 x 10⁻¹⁰ x 10¹² Pico liters

**Volume of bacteria cell into Pico liters = 60.27 Pico liters**

Calculate the speed of a marble that rolls 9 cm in 4 seconds

### Answers

**Answer:**

2.25

**Explanation:**

9/4

What is the IUPAC name for the following compound?

CH3-CH2-CH2-CH2-CH2-CH2 -CH2-CH3

Enter the name of the molecule.

### Answers

8 carbon chain, octane

What is the mole fraction of KCI in a

mixture of 0.564 g NaCl, 1.52 g KCI,

and 0.857 g LiCl?

Molar Mass

NaCl: 58.44 g/mol

KCI: 74.55 g/mol

Lici: 42.39 g/mol

### Answers

Answer:

Mole fraction of KCl = 0.4056

Explanation:

We'll begin by calculating the number of mole of each compound. This can be obtained as follow:

For NaCl:

Mass NaCl = 0.564 g

Molar mass of NaCl = 58.44 g/mol

Mole of NaCl =?

Mole = mass /Molar mass

Mole of NaCl = 0.564 / 58.44

Mole of NaCl = 0.0097 mole

For KCl:

Mass KCl = 1.52 g

Molar mass of KCl = 74.55 g/mol

Mole of KCl =?

Mole = mass /Molar mass

Mole of KCl = 1.52 / 74.55

Mole of KCl = 0.0204 mole

For LiCl:

Mass LiCl = 0.857 g

Molar mass of LiCl = 42.39 g/mol

Mole of LiCl =?

Mole = mass /Molar mass

Mole of LiCl = 0.857 / 42.39

Mole of LiCl = 0.0202 mole

Next, we shall determine the total mole in the mixture. This can be obtained as follow:

Mole of NaCl = 0.0097 mole

Mole of KCl = 0.0204 mole

Mole of LiCl = 0.0202 mole

Total mole =?

Total mole = Mole of NaCl + Mole of KCl + Mole of LiCl

Total mole = 0.0097 + 0.0204 + 0.0202

Total mole = 0.0503 mole

Finally, we shall determine the mole fraction of KCl in the mixture. This can be obtained as follow:

Mole of KCl = 0.0204 mole

Total mole = 0.0503 mole

Mole fraction of KCl =?

Mole fraction of KCl = Mole of KCl /Total mole

Mole fraction of KCl = 0.0204 / 0.0503

Mole fraction of KCl = 0.4056

**Answer:**

.4 is correct

**Explanation:**

What would be the mass in amu of 150 atoms of carbon?

### Answers

**Answer:**

Do you mean the periodic table? The atomic mass of carbon is 12 and oxygen is 16.

If I understand you right though, what you’re looking for is what oxygen’s mass would be in a certain unit of measurement with which carbon weighs 150 units.

In regular atomic mass units carbon’s mass is 12 and oxygen’s is 16, so oxygen’s mass is 4/3 times carbon’s mass. In our new unit of measurement where carbon weights 150 units, oxygen would weigh 150 * 4/3 = 200 units.

what is a 7 letter word that starts with f: Ancient plants and animals formed into rocks.

### Answers

**Answer:**

Fossils?

**Explanation:**

A group of students is setting up a test to see whether earthworms, like those shown in the photo, prefer rough or smooth surfaces

### Answers

**Answer:**

they like smooth

**Explanation:**

How many moles are in 2.5L of 1.75 M Na2CO3

### Answers

Answer:

4.375 moles Na2CO3

Explanation:

Formula for molarity is;

M = n/V

Where;

M is molarity

n is number of moles

V is volume

Making n the subject we have;

n = VM

We are given;

M = 1.75 M

V = 2.5 L

Thus;

n = 2.5 × 1.75

n = 4.375 moles Na2CO3

**Answer:**

4.375 moles Na2CO3

**Explanation:**

Have a great day

Using Graham's Law of Effusion, calculate

the approximate time it would take for

1.0 L of argon gas to effuse, if 1.0 L of

oxygen gas took 12.7 minutes to effuse

through the same opening.

0.070 minutes

0.89 minutes

None of the other answers

14 minutes

12 minutes

### Answers

The** rate** of **effusion** of **Argon **here is 8.03 min

Data;

Molar mass of Oxygen = 16g/molTime for effusion of oxygen = 12.7 minMolar mass of Argon = 40g/molTime for effusion of Argon = ?

Graham's Law of Effusion

This law states that the** rate **of **effusion** of a **gas** is inversely proportional to the **square root** of it's **molar mass**.

[tex]R \alpha \frac{1}{\sqrt{M} }[/tex]

From this,

[tex]\frac{r_1}{r_2} = \frac{\sqrt{M_2} }{M_1}[/tex]

substituting the values and solving,

[tex]\frac{R_A_r}{12.7}= \frac{\sqrt{16} }{\sqrt{40} } \\ R_A_r = \frac{12.7*\sqrt{16} }{\sqrt{40} } \\R_A_r = 8.032min[/tex]

The** rate** of **effusion** of **Argon **here is 8.03 min

Learn more on** Graham's law of effusion** here;

https://brainly.com/question/12211278

All forms of energy can be traced back to

### Answers

the answer is the sun