HELP WITH QUESTION 3,4 and 5 PLEASE

Answer:

6.9

Explanation:

Mass(m)=?

Density (D)=0.75

Volume (v)=9.2

M=D×V

M=0.75×9.2

M=6.9

Answer:

Write the empirical formula of at least four binary ionic compounds that could be formed from the following ions: Ca^2 , Al^3 ,I^-,S^2-

Explanation:

1)Formula of calcium iodide:

The compound of Ca^2+ and I^-1:

[tex]CaI_2[/tex]

2) Formula of calcium sulfide:

[tex]CaS[/tex]

3) Formula of aluminum iodide:

[tex]AlI_3[/tex]

4) Formul aluminum sulfide:

[tex]Al_2S_3[/tex]

These are the four ionic compounds that are formed.

Answer: The atomic radius of iron is 128 pm.

Explanation:

To calculate the radius of the metal having FCC crystal lattice, the relationship between edge length and radius follows:

[tex]4r=\sqrt{2}a[/tex]

Where,

a = edge length = 362 pm

r = atomic radius of iron = ?

Plugging values in above equation, we get:

[tex]r=\frac{\sqrt{2}\times 362}{4}\\\\a=128pm[/tex]

Hence, the atomic radius of iron is 128 pm.

Answer: The molar mass of protein A is 3023.41 g/mol.

Explanation:

To calculate the osmotic pressure, we use the formula:

[tex]\pi=i\times M\times R\times T[/tex]

              OR

[tex]\pi=i\times \frac{\text{Given mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution}}\times R\times T[/tex]      .....(1)

Where,

[tex]\pi[/tex] = osmotic pressure = 0.285 atm

i = 1

Given mass of protien (solute) = 54.1 mg = 0.0541 g        (Conversion factor: 1 g = 1000 mg)

Volume of solution = 1.5 mL

R = Gas constant = 0.0821 L.atm/mol.K

T = temperature = [tex]18^oC=[18+273]=291K[/tex]

Plugging values in equation 1:

[tex]0.285atm=1\times \frac{0.0541\times 1000}{\text{Molar mass of protein}\times 1.5}\times 0.0821L.atm/mol.K\times 291K\\\\\text{Molar mass of protein}=\frac{1\times 0.0541\times 1000\times 0.0821\times 291}{0.285\times 1.5}\\\\\text{Molar mass of protein}=3023.41g/mol[/tex]

Hence, the molar mass of protein A is 3023.41 g/mol.

The molar mass of the protein is  3018 g/mol.

We know that the osmotic pressure is obtained using the formula;

Osmotic pressure = iMRT

concentration of the  protein = 54.1 * 10^-3g/M/ 1.5 * 10^-3 L

Where M = molar mass of the protein

So;

0.285 atm =  54.1 * 10^-3g/ 1.5 * 10^-3 L M * 0.0821 L.atm/mol.K * 291 K

0.285  = 1.29/1.5 * 10^-3M

M = 1.29/0.285 * 1.5 * 10^-3

M = 3018 g/mol

Learn more about osmotic pressure: https://brainly.com/question/4631715

Answer:

lithium 3

Explanation:

This is because lithium has three protons

Answer:

0.012288122055459

Explanation:

i might be wrong

Answer:

If the density of the material is equal to the density of the material you have been working with it is possible that the samples are the samples

Explanation:

Density is an intensive property of the matter (Doesn't depends of its amount) that is widely used to identify a substance. Density is the ratio between the mass of the substance (In this case 25.62g) and the volume this amount occupies (21.9cm³). The density is:

25.62g / 21.9cm³ =

1.17g/cm³.

29.26 gram

Explanation:

No of molecules = no of mole × Avogadro's number

No of molecules = mass in gram/ molar mass × Avogadros number

Mass in gram =No of molecules×molar mass / Avogadros number

Mass in gram = 3.012 ×10^23 × 58.5/6.02×10^23

29.26 gram

Answer:

Answer is in the explanation.

Explanation:

Before the equivalence point, the pH of the solution of HCl that is titrated with NaOH has a pH <<< 7. When you are adding more NaOH nearing, thus, to the equivalence point the change in pH occurs quickly, and, with 1 drop of excess of NaOH after equivalence, the pH of the solution change to a pH >>> 7

That means the volume added at pH 5 or pH 9 is, almost, the same doing the indicator work just as well as an indicator with change color at pH 7

Answer:

12.00 g C-12 = 1 mol C-12 atoms = 6.022 × 1023 atoms • The number of particles in 1 mole is called Avogadro's Number (6.0221421 x 1023).

Explanation:

carry on learning

Answer:

12 mol CO₂

General Formulas and Concepts:

Atomic Structure

Stoichiometry

Explanation:

Step 1: Define

Identify

[rxn] 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

[Given] 2 mol C₆H₁₂O₆

[Solve] mol CO₂

Step 2: Identify Conversions

[rxn] 6CO₂ → C₆H₁₂O₆

Step 3: Convert

Answer:

Sorry I didn't get it

Explanation:

Where is the question?

Answer:

37.09 g of B₅H₉ is required to form 148 g of  borate salt( Na₂B₄O₇  )

Explanation:

Given the data in the question;

B₅H₉ → H₃BO₃ → Na₂B₄O₇

find the mass (in grams) of B5H9 required to form 148 g of the borate salt by this reaction sequence.

S                                M.W

B₅H₉                          63

H₃BO₃                       62

Na₂B₄O₇                   201

So, moles of Na₂B₄O₇  = 148 / 201 = 0.736

Since Boron will be conserved,

Moles of Boron atoms in Na₂B₄O₇  will be;

⇒ 4 × 0.736 = 2.944

Now, Moles of Boron in Na₂B₄O₇ = Moles of Boron in H₃BO₃ = Moles of Boron in B₅H₉  

Hence,

Moles of Boron in B₅H₉ = 2.944

Moles of B₅H₉ = 2.944 / 5 = 0.5888

Mass of B₅H₉ = 0.5888 × 63 = 37.09 g

Therefore, 37.09 g of B₅H₉ is required to form 148 g of  borate salt( Na₂B₄O₇  )

Answer:

babies have the most sensitive taste buds

Answer:

1.1 × 10² g

Explanation:

The combustion of gasoline releases energy that is used to move the car. The enthalpy of reaction (ΔH°rxn) of the combustion of gasoline is 47 kJ/g, that is, 47 kiloJoule are produced per gram of gasoline burned. The mass of gasoline to be burned to release 5,375 kJ is:

5,375 kJ × 1 g Gasoline/47 kJ = 1.1 × 10² g

Explanation:

Correct option is

B

0.750 M

Na3PO4 dissociates as:

Na3PO4⇌3Na++PO43−

∴ conc. of Na+ would be =3×0.250=

hope help

Answer:

C. Y & Z

Explanation:

V, W are imaginary metals here because their valence electrons are typically less than 4. X, Y, Z are non-metals and have higher valence electrons. Here, if V or W bind with X, Y, or Z we make ionic bond (because metal + non metal = ionic). But, if X binds with Y or Z or any combinations of any two of the three non-metals results in covalent bond (non metal + non metal = covalent).

Thus, Y and Z make covalent.

Answer:

0.85 M

Explanation:

Step 1: Given data

Step 2: Calculate the moles (n) corresponding to 660 g of calcium phosphate (solute)

We will use the following expression.

n = m/M

n = 660 g/(310.18 g/mol) = 2.13 mol

Step 3: Calculate the molar concentration (molarity) of the solution

Molarity is equal to the moles of solute divided by the liters of solution.

M = 2.13 mol/2.5 L = 0.85 M

Answer:

See explanation

Explanation:

From the parameters provided;

V=?

n= 1.46 moles

P= 0.982 ATM

T= 13°C + 273 = 286 K

R = 0.0821 L.atm/mol.K

From

PV= nRT

V= nRT/P

V= 1.46 × 0.0821 × 286/0.982

V= 34.9 L

b) Boyle's law states that, the pressure of a given mass of gas is inversely proportional to its volume at constant temperature and pressure. This statement is a correct postulation about ideal gases which can be arrived at from the kinetic theory of gases.

Answer:

No, the product is not chiral

Explanation:

The compound (S)-3-Methylhexane is chiral. However, the bromination of this compound via free radical mechanism yields an achiral intermediate as shown in the image attached to this answer.

This achiral intermediate is a flat and planar tertiary radical. Attack on either face of this radical specie is possible. This leads us to obtain a 50-50 mixture of (R) and (S) - 3-bromo-3-methylhexane.

This is a racemic mixture hence it is optically inactive.

Answer:

1) increases

2) decrease

3) increase

4) decrease

Explanation:

When ionic compounds dissolve in water, the concentration of ions in solution increases since ionic substances dissociate into ions in solution. The greater the concentration of ions in a solution, the greater the ionic strength of that solution.

Hence, if HNO3 is added to KOH solution, the ionic strength of the solution is increased due to an increase in the number of ions in the solution.

Also, when benzoic acid is titrated against KOH, potassium benzoate (an ionic substance) is formed thereby increasing the ionic strength of the solution.

However, when KOH is added to CaCl2, a precipitate (Ca(OH)2) is formed. Also, when NaOH is added to FeCl2, a precipitate (Fe(OH)2) is formed. In both cases, the formation of the precipitate decreases the concentration of ions in the solution thereby decreasing the ionic strength of the solution.

Answer:

Copper(I) chloride, commonly called cuprous chloride, is the lower chloride of copper, with the formula CuCl.

Explanation:

Answer:

[tex]\% m=40.46\%[/tex]

Explanation:

Hello there!

in this case, according to the given information, it turns out firstly necessary for us to write up the chemical equation as shown below:

[tex]BaCl_2+Na_2SO_4\rightarrow BaSO_4+2NaCl[/tex]

Thus, we calculate the mass of BaCl2 stoichiometrically related to the produced 1.658 g of precipitate in order to discard it from the sample:

[tex]m_{BaCl_2}=1.658gBaSO_4*\frac{1molBaSO_4}{233.38 gBaSO_4} *\frac{1molBaCl_2}{1molBaSO_4}*\frac{208.23 gBaCl_2}{1molBaCl_2}\\\\m_{BaCl_2}=1.479gBaCl_2[/tex]

Thus, the mass percentage is calculated as shown below:

[tex]\% m=\frac{1.479g}{3.656g}*100 \% \\\\\% m=40.46\%[/tex]

Regards!

Explanation:

A kind of chemical reaction in which a reaction between any combustible substance and an oxidizer takes place in order to form an oxidized product.

Eg: Fuel + O2 → CO2 + H2O.

The burning of charcoal is a combustion reaction.

A synthesis reaction occurs when two or more reactants combine to form a single product.

Eg: Na + Cl → NaCl

An example of a synthesis reaction is the combination of sodium (Na) and chlorine (Cl) to produce sodium chloride (NaCl).

A decomposition reaction occurs when one reactant breaks down into two or more products.

Eg: NaCl → Na + Cl

An example of a decomposition reaction is the breakdown of Sodium chloride to give sodium and chloride.

A single replacement reaction, sometimes called a single displacement reaction, is a reaction in which one element is substituted for another element in a compound.

Eg: Zn + 2 HCl → 2 ZnCl + H2

The reaction between zinc metal and hydrochloric acid to produce zinc chloride and hydrogen gas is an example of a single-displacement reaction.

A double replacement reaction is a type of chemical reaction that occurs when two reactants exchange cations or anions to yield two new products.

Eg: AgNO 3 + NaCl → AgCl + NaNO

The reaction between silver nitrate and sodium chloride to produce silver chloride and sodium nitrate is an example of a double-displacement reaction.

Answer:   aaaaaaaaaaa

The basic SI unit for volume is the cubic meter (m3), but smaller volumes may be measured in cm3, and liquids may be measured in liters (L) or milliliters (mL).

Explanation: