what is the mass percentage of kbr for a solution that is created by dissolving 3.44 (0.0289 moles) of kbr in 6.22 (0.345 moles) of h20

Answer:

For example, the atomic radius of the metal zirconium, Zr, (a period-5 transition element) is 155 pm (empirical value) and that of hafnium, Hf, (the corresponding period-6 element) is 159 pm. ... The increase in mass and the unchanged radii lead to a steep increase in density from 6.51 to 13.35 g/cm3.

Explanation:

Answer: Boron is the element which has properties of both metals and nonmetals.

Explanation:

Metals are defined as the elements which loose electrons to attain stable electronic configuration. They attain positive charge and form cation. Example: Zinc (Zn), Aluminium (Al) , copper (Cu)

Non-metals are defined as the elements which gain electrons to attain stable electronic configuration. They attain negative charge and form anion. Example: Chlorine (Cl) , Sulphur (S)

Metalloids are defined as the elements which show properties of both metals and non-metals. There are 7 metalloids in the periodic table. They are Boron (B) , Silicon (Si) , Germanium (Ge) , Arsenic (As) ,  Antimony (Sb), Tellurium (Te) and Polonium (Po).

Thus boron is the element which has properties of both metals and nonmetals.

Answer:

The answer is A boron!!!!!!

Explanation:

i took the quiz on ed

Hot water stays on the top of cold water and doesn't mix. This is because of difference in DENSITY of water at different temperatures.

When we heat water, then the atoms gain energy from the heat and start moving away from each other. Now, when the atoms move away from each other than the (mass per unit volume) i.e. the density decreases. This makes water lighter.

When the temperature is less i.e. cold water then the atoms are more compactly packed and therefore the density of water is more at lower temperatures.

Since, hot water is lighter than cold water that is why it stays on top of the cold water.

The given model shows the covalent bond.

A covalent bond includes the mutual sharing of one or more pairs of electrons among atoms. these electrons are concurrently attracted via the 2 atomic nuclei. A covalent bond bureaucracy when the difference among the electronegativities of atoms is just too small for an electron transfer to arise to form ions.

A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. these electron pairs are referred to as shared pairs or bonding pairs. The stable stability of appealing and repulsive forces between atoms, once they share electrons, is known as covalent bonding.

Learn more about covalent bonds here:-https://brainly.com/question/3447218

#SPJ1

Nothing happens if the iron rod is inserted into the nitrogen. However, when the iron rod is suspended in the air.

A non-metal, nitrogen is. As a result, it typically interacts with metals to create ionic compounds. Only when the reactants produce products that allow the system as a whole to release energy does the reaction take place. If the system requires energy to undergo the reaction, the reaction cannot take place. When iron is exposed to oxygen and moisture for an extended length of time, a process known as iron oxide occurs. At the atomic level, oxygen bonds to iron to produce the complex known as an oxide, which weakens the metal bond.

The complete question is - If a piece of pure iron is placed in pure nitrogen, nothing happens. If the iron is exposed to air, it begins to rust. What conclusion can you make about air, based on this observation?

Learn more about nitrogen here-

https://brainly.com/question/16711904

#SPJ9

The temperature at which the equilibrium constant for the given reaction is equal to 2.6.

To find the temperature at which the equilibrium constant for the reaction 2 NO2(g) ⇌ N2O4(g) is equal to 2.6, you can use the van't Hoff equation:ln(K2/K1) = -(ΔH/R) × (1/T2 - 1/T1)Where K1 and K2 are the equilibrium constants at temperatures T1 and T2, respectively, ΔH is the enthalpy change of the reaction, and R is the gas constant (8.314 J/mol·K).Given: K1 = 8.8 at T1 = 298 K, K2 = 2.6 (the desired equilibrium constant), and ΔH = -57.2 kJ/mol.First, convert ΔH to J/mol: ΔH = -57,200 J/mol.

Now, you can plug the values into the van't Hoff equation:ln(2.6/8.8) = -(-57,200 J/mol) × (1/T2 - 1/298 K) / (8.314 J/mol·KAfter solving for T2, you will find the temperature at which the equilibrium constant for the given reaction is equal to 2.6.

Learn more about  equilibrium constant here:https://brainly.com/question/3159758

#SPJ11

Answer:

sulfur and water

Explanation:

sulfur + water --> sulfuric acid

^ reactants. ^ product

The correct answer is 107.9 g of Ag is produced from a reaction of 31. 75 gram of Copper.

Molar mass of a substance is the mass in grams of one mole of the compound. A mole is the measurement of the number of things, such as atoms, molecules, and ions, that are present in a substance. Any material has 6.022 x 1023 molecules in a mole, it is known as Avogadro's number . The mole is used to determine the size of the tiniest entities quantitatively, just as we use a standard value to quantify many things, such as 1 dozen = 12 items.

Formula - Molar mass = mass in grams/mole = g/mol

Molar mass of a substance can be calculated as:

Given,

n = W/M, where

W = required mass

M= molar mas

Given chemical reaction is:

Cu + 2AgNO₃ → Cu(NO₃)₂ + 2Ag

From the stoichiometry of the reaction,

1 mole of Cu = produce 2 moles of Ag

Given mass of Cu = 31.75g

Molar mass of Cu = 63.5g/mol

Moles of Cu = 31.75g / 63.5g/mol = 0.5 moles

0.5 moles of Cu = produce 2×0.5 = 1 mole of Ag

Molar mass of Ag = 107.9g/mol

Required mass of Ag = 1mol × 107.9g/mol = 107.9 g

To know more about Molar Mass, refer to:

brainly.com/question/837939

#SPJ4

We need 2.0 L of the 6.0 M KNO3 stock solution to make 10.0 L of a 1.2 M KNO3 solution.

To find the volume of the stock solution needed to make 10.0 L of a 1.2 M KNO3 solution, you can use the dilution equation:
MIVI=M2V2 or,
C1V1 = C2V2
where C1 and V1 are the concentration and volume of the stock solution (KNO3), and C2 and V2 are the concentration and volume of the diluted solution.

Given:
C1 = 6.0 M (concentration of the stock solution)
C2 = 1.2 M (concentration of the diluted solution)
V2 = 10.0 L (volume of the diluted solution)
We need to find V1 (volume of the stock solution needed). Rearrange the equation to solve for V1:
V1 = (C2V2) / C1
Plug in the given values:
V1 = (1.2 M × 10.0 L) / 6.0 M
V1 = 12.0 L / 6.0
V1 = 2.0 L
Therefore, you need 2.0 L of the 6.0 M KNO3 stock solution to make 10.0 L of a 1.2 M KNO3 solution.

Learn more about concentration : https://brainly.com/question/17206790

#SPJ11

Answer:

Submerge it in a liquid and measure the change in volume.

Explanation:

If you submerge a irregular solid in water (for example), if you measure the initial volume reading, and the final volume reading after the solid is submerged, you can use the change in volume to calculate the volume of the solid because the change in volume equals the volume of the solid.

Answer:

23.4 x 10¹²mm

Explanation:

 Given problem;

  Convert Gm to mm;

   Gm  = Gigameters

    mm  = millimeters

   1 Gigameter  = 1 x 10⁹m

    1000mm = 1 m

To convert from Gm to mm;

       23.4 Gm x \(\frac{1 x 10^{9} m}{1Gm}\) x \(\frac{1000mm}{1m}\)   = 23.4 x 1 x 10⁹ x 10³   =

                                                    = 23.4 x 10¹²mm

Answer:

Read below

Explanation:

Melanoma -- the most virulent form of skin cancer -- is caused by harmful ultraviolet light from the sun. Australia's proximity to Antarctica, where there is a hole in the ozone layer that filters out UV rays, also increases the risk.

Answer:

In Austrailia there is the hieghest rate of skin cancer because there is so much sunlight in Austrailia and there some people that have sensitive skin and they get skin cancer easily/ fast.

Explanation: This answer is correct because my teacher gave me this answer.

Hope this was helpful if not plz don't report my answer plz.

Answer:

Impurities and temperatures

Explanation:

Answer:

1. Foods that have changes that are chemically introduced.

2. corn soybeans apples etc

3. sot they last longer or look better

4. new dna is placed in them and their seeds

5. they are not as good for humans

Explanation:

Rutherford's model of atom could not explain chemical properties as it did not make any mention as to how chemical changes take place.

These properties are defined as those properties which become evident during or after a chemical reaction after the identity of the substance is changed during chemical reaction.

These properties cannot be determined externally just by viewing the substance ,these change immensely after a substance undergoes a chemical change.These are used for identification of unknown substances and for building up chemical classifications.

The major chemical properties are flammability,toxicity,reactivity,acidity and heat of combustion.For a chemical property to be apparent , it is necessary that the structure of the substance is altered.

Learn more about chemical properties,here:

https://brainly.com/question/5186976

#SPJ1

Answer:

\(\boxed {\boxed {\sf 0.3375 \ mol \ NaCl}}\)

Explanation:

Molarity is found by dividing the moles of solute by liters of solution.

\(M=\frac{moles \ of \ solute }{liters \ of \ solution}\)

We know the molarity is 0.45 M and there are 0.750 liters of solution. The solute is NaCl (sodium chloride). We can substitute the values into the formula.

\(0.45 \ M = \frac{ moles \ of \ NaCl}{ 0.750 \ L }\)

The molarity (M) can also be represented by mol/L

\(0.45 \ mol/L = \frac{ moles \ of \ NaCl}{ 0.750 \ L }\)

We are solving for the moles of solute, so we must isolate the numerator. It is being divided by 0.750 liters. The inverse operation is multiplication, so multiply both sides of the equation by 0.750 L.

\(0.750 \ L * 0.45 \ mol/L = \frac{ moles \ of \ NaCl}{ 0.750 \ L }*0.750 \ L\)

The liters will cancel out.

\(0.750 * 0.45 \ mol = { moles \ of \ NaCl}\)

\(0.3375 \ mol \ = moles \ of NaCl\)

There are 0.3375 moles of NaCl in a 0.750 liter solution with a molarity of 0.45 M.

The mass of water produced if the percent yield of the reaction is 72% is 16.2g.

Mass of acetylene = 40.0 grams

Mass of oxygen = 40.0 grams

Percent yield of the reaction = 72%

The balanced chemical equation is : 2 C2H2(g) + 5 O2(g) → 4 CO2(g) + 2 H2O(g)

From the balanced chemical equation, it is clear that 2 moles of acetylene reacts with 5 moles of oxygen to form 2 moles of water.

To find out limiting reagent

Moles of acetylene = Given mass of acetylene / molar mass of acetylene

                                 = 40.0 g / 26 g/mol = 1.54 moles

Moles of oxygen = Given mass of oxygen / molar mass of oxygen

                                = 40.0 g / 32 g/mol = 1.25 moles

The limiting reactant is oxygen because its number of moles is less than acetylene. Oxygen will react with 1.25 moles of acetylene present and form CO2 and H2O.

According to the balanced equation, the stoichiometric ratio of C2H2 to H2O is 2:2, meaning that for every 2 moles of C2H2, 2 moles of H2O are produced.

Since the stoichiometry is 1:1, the moles of water produced will be the same as the moles of acetylene used.

The number of moles of H2O produced 1.25 moles.

The mass of H2O produced = Number of moles of H2O × Molar mass of H2O

Mass of H2O produced = 1.25 × 18 = 22.5 g

Given percent yield = 72%

The actual yield can be calculated as follows;

Percent yield = Actual yield / Theoretical yield × 100

72% = Actual yield / 22.5 g × 100

Actual yield = 22.5 g× 72 / 100 =16.2 g

Thus, the mass of water produced if the percent yield of the reaction is 72% is 16.2g.

To learn more about acytelene :

https://brainly.com/question/19872772

#SPJ11

A) The balanced equation for the reaction of solid silicon dioxide with hydrofluoric acid is SiO₂(s) + 4 HF(aq) ⟶ SiF₄(g) + 2 H₂O(l).

B) The complete and net ionic equations for the reaction of calcium chloride and sodium fluoride is:

Ca²⁺(aq) + 2 Cl⁻(aq) + 2 Na⁺(aq) + 2 F⁻(aq) ⟶ CaF₂(s) + 2 Na⁺(aq) + 2 Cl⁻(aq) and

Ca²⁺(aq) + 2 F⁻(aq) ⟶ CaF₂(s), respectively.

A) The reaction between silicon dioxide and hydrofluoric acid can be written as follows:

SiO₂(s) + 4 HF(aq) ⟶ SiF₄(g) + 2 H₂O(l)

The reaction produces silicon tetrafluoride gas and liquid water. Four moles of hydrofluoric acid are required for each mole of silicon dioxide consumed. The balanced equation includes the state symbols for each reactant and product.

B) The balanced molecular equation for the reaction between calcium chloride and sodium fluoride in aqueous solution is:

CaCl₂(aq) + 2 NaF(aq) ⟶ CaF₂(s) + 2 NaCl(aq)

The reaction produces solid calcium fluoride and aqueous sodium chloride. The reaction is a double displacement reaction in which the calcium cation and the sodium cation exchange anions.

The complete ionic equation is:

Ca²⁺(aq) + 2 Cl⁻(aq) + 2 Na⁺(aq) + 2 F⁻(aq) ⟶ CaF₂(s) + 2 Na⁺(aq) + 2 Cl⁻(aq)

The balanced molecular equation is shown on the left, and the separated aqueous ions are shown on the right.

Only the species that appear in both the reactant and product side are spectator ions, which are crossed out to obtain the net ionic equation.

Net ionic equation:

Ca²⁺(aq) + 2 F⁻(aq) ⟶ CaF₂(s)

Solid calcium fluoride and aqueous sodium chloride are the only products of the net ionic equation.

Learn more about Net ionic equation here: https://brainly.com/question/25604204

#SPJ11

Answer:

183.84 u

Explanation:

W (also known as "Tungsten") atomic number is 74 and atomic mass is   183.84 u

NO₂ , SO₃ and CO are covalent compounds and LiCl is ionic in nature.

The definition of an ionic compound is chemical compound composed of ions which is held together by electrostatic forces i.e. held together by ionic bonds. They are formed by ions of opposite charge. The compound is neutral but it consists of a positively and negatively charged cations and anions.

Learn more about ionic compounds at https://brainly.com/question/2687188

#SPJ10

Answer:

17.51M

Explanation:

first we make out what we've been given .

Mass of ethanol= 91.9g

volume of water = 481.0ml

volume of solution= 597.5ml

density of water = 1.0g/ml

density of ethanol= 0.789g/ml.

firstly find the volume of ethanol since the total volume of the solution is 597.5ml and we've been given the volume of water which is 481.0ml , we subtract the volume of water from the volume of the solution , to find out the volume of ethanol .

volume e =597.5ml - 481.0ml

= 116.5ml

Then we find the molecular mass of ethanol , which is 45.04g/mol .

then we find the number of moles of ethanol .

n=mass /molar mass

=91.9g/ 45.04g/mol

=2.04mols .

Then convert the volume from milliliters to liters , by dividing by a 1000 .

v= 116.5/1000

=0.1165L

since we have our number of moles and volume , we can now find the molarity . which is

M=n/v

= 2.04mols /0.1165L

= 17.51M .

The solution could be an acid. Acids conduct electrical current poorly and turn blue litmus paper red due to their ability to donate protons (H+) to the litmus paper, causing a change in color.

Acids have a pH less than 7 and are known for their sour taste and corrosive properties. They typically contain hydrogen ions (H+) and have a higher concentration of positive ions, making them inefficient conductors of electricity compared to bases or salts. The reaction between the acid and the litmus paper indicates the presence of hydrogen ions, which leads to the color change. Examples of acids include hydrochloric acid (HCl) and sulfuric acid (H2SO4). turn blue litmus paper red due to their ability to donate protons (H+) to the litmus paper, causing a change in color.

learn more about Acids here:

https://brainly.com/question/29796621

#SPJ11

Answer:

C12H22O11

Explanation:

After shaking with D₂O, the spectrum of ethanol shows two proton signals. The OH signals will no longer exist.

Three peaks may be seen in the ethanol 1H-NMR spectra. The following are the chemical shifts (Image 1).

The spectrum of ethanol after shaking with D₂O shows only two peaks. After shaking with D₂O, the peak that corresponds to OH disappears at this point. The following are the chemical shifts (Image 2).

At around 3.57 ppm, a water peak forms while the -OH resonance totally vanishes. This happens as a result of leftover H₂O and HOD in the D₂O bottle and traded out hydroxy protons (-OH), which now produce more H₂O.

Find more on 1H-NMR spectra at : brainly.com/question/10722669

#SPJ4

The molal freezing point of the unknown solvent is 3.9 °C/mol kg.

Given to us is the solution freezes at 7.8 degrees Celsius below its normal freezing point,

To determine the molal freezing point depression, we need to use the formula:

ΔTf = Kf × m

Where:

ΔTf is the freezing point depression,

Kf is the cryoscopic constant (a property of the solvent),

m is the molality of the solution (moles of solute per kilogram of solvent).

Substituting the values into the equation:

7.8 °C = Kf × m

Since we have 2 moles of the solute dissolved in 1 kg of the solvent, the molality (m) is calculated as:

m = moles of solute / mass of solvent

m = 2 mol / 1 kg

m = 2 mol/kg

Now we can rearrange the equation to solve for Kf:

Kf = ΔTf / m

Kf = 7.8 °C / (2 mol/kg)

Kf = 3.9 °C/mol kg

Therefore, the molal freezing point of the unknown solvent is 3.9 °C/mol kg.

Learn more about freezing point depression here:

https://brainly.com/question/30093051

#SPJ 4

Answer:

Aluminum

Explanation

The volume of the metal is found by subtracting the final volume by the Intel volume giving 7

And the formula for density is mass divided by volume hence minus 7 by 18.9 giving 2.7

The molar mass of MgI2 is the sum of masses of 1 mol of Mg and 2 mol of I. Option A.

Molecular weight is the mass of a particular molecule and is measured in Daltons. Different molecules of the same compound can have different molecular weights because they contain different isotopes of the element. The molar mass of a substance is the mass in grams of one mole of the substance.

The molar mass of a substance can be obtained by adding the molar masses of the atomic components. The calculated molar mass can then be used to convert the mass and number of moles of the substance. Use the chemical formula to find the number of atoms for each element in the compound.

Learn more about Molar Mass here:-  https://brainly.com/question/837939

#SPJ4

Answer:

0.544 M

Explanation:

First find the moles in the final solution

0.8 mols/L *1.7L

1.36 mols

so there is 1.36 mols in 2.5L

concentration will be 1.36/2.5

0.544 M

According to molar concentration , the original concentration of solution is 0.544 M.

Molar concentration is defined as a measure by which concentration of chemical substances present in a solution are determined. It is defined in particular reference to solute concentration in a solution . Most commonly used unit for molar concentration is moles/liter.

The molar concentration depends on change in volume of the solution which is mainly due to thermal expansion. Molar concentration is calculated by the formula, molar concentration=mass/ molar mass ×1/volume of solution in liters.

In terms of moles, it's formula is given as molar concentration= number of moles /volume of solution in liters.In case of 2 solutions , it is calculated as, M₁V₁=M₂V₂

On substitution, M₁=0.8×1.7/2.5=0.544 M.

Thus,the original concentration of solution is 0.544 M.

Learn more about molar concentration,here:

https://brainly.com/question/21841645

#SPJ2