Students are asked to design an experiment with cookies to demonstrate their understanding of the scientific method. One group has decided to determine the amount of time it will take for a cookie to "dissolve" in a glass of milk.

Which variable would most likely NOT affect the time it takes for the cookie to dissolve?

a) the size of the cup of milk
b) the type of cookie
c) the number of students in the group
d) the temperature of the milk
e) the type of milk​​

Answer:

2.82 g

Explanation:

Step 1: Write the balanced precipitation reaction

3 Ba(NO₃)₂ (aq) + Al₂(SO₄)₃ (aq) ⇒ 3 BaSO₄(s) + 2 Al(NO₃)₃(aq)

Step 2: Calculate the reacting moles of Ba(NO₃)₂

45.0 mL (0.0450 L) of 0.548 M Ba(NO₃)₂ react.

0.0450 L × 0.548 mol/L = 0.0247 mol

Step 3: Calculate the moles of Al₂(SO₄)₃ that react with 0.0247 moles of Ba(NO₃)₂

The molar ratio of Ba(NO₃)₂ to Al₂(SO₄)₃ is 3:1. The reacting moles of Al₂(SO₄)₃ are 1/3 × 0.0247 mol = 8.23 × 10⁻³ mol

Step 4: Calculate the mass corresponding to 8.23 × 10⁻³ moles of Al₂(SO₄)₃

The molar mass of Al₂(SO₄)₃ is 342.2 g/mol.

8.23 × 10⁻³ mol × 342.2 g/mol = 2.82 g

Answer:

c

Explanation:

The correct answer is

C. -432.4 J/mol K

Answer:

one parent

Explanation:

As one parent cell divides it into two daughter cells and so on.

Explanation:

Facilitar el movimiento y desplazamiento de objetos pesados reduciendo el rose del objeto contra el suelo, Obtener un movimiento circular por efecto de la fuerza de un liquido, en el caso de contadores, molinos, centrales hidroeléctricas y turbinas.

Transmitir el movimiento de un eje a otro como en el caso de las lavadoras, bicicletas y neveras. Reducir drásticamente el esfuerzo necesario para elevar y mover objetos, como en casos de pozos de agua y ascensores Transformar movimientos giratorios en otros movimientos o viceversa. ,

[tex] \huge \mathrm{ \underline{Answer} ࿐}[/tex]

The correct option is B.

A Catalyst is a chemical which promotes or speed up a chemical reaction without undergoing any chemical reaction itself.

for example : potassium permanganate - Hydrogen peroxide will decompose into water and oxygen gas in the presence of KMnO4.

_____________________________

[tex]\mathrm{ \#TeeNForeveR}[/tex]

Carbon has an outer shell consisting of 4 valence electrons. ... Thus, a carbon ion can have a charge of anywhere from -4 to +4, depending on if it loses or gains electrons. Although the most common oxidation states of carbon are +4 and +2, carbon is able to make ions with oxidation states of +3, +1, -1, -2, and -3.

Answer:

See explanation.

Explanation:

Hello there!

3. In this case, according to the given question, it turns out possible for us to say that any chemical formula, for an ionic compound, has the cation (positive) on the left and the anion (negative) on the right; thus, since Mg is a metal, which tends to lose electrons and become positively charged whereas the Cl is a nonmetal, which tends to gain electrons and become negatively charged, we have the following:

[tex]Mg^{2+}Cl^-\\\\Mg^{2+}Cl^-_2\\\\MgCl_2[/tex]

4. In this case, since lithium is a metal, as well as magnesium, it is not possible for them to switch around their charges as they will not be bonded because they will be repelled rather than attracted because of their equal positive charges.

Regards!

Answer:

Answer: Number of moles of KOH present in solution is 3.75.

Explanation:

0.1 moles

There are 0.1 moles of solute in 250 mL of 0.4 M solution.

1 Answer. 1 mol of NaOH

Answer:

1.96 × 10²⁴ molecules

Explanation:

Step 1: Given data

Mass of ethanol (m): 150. g

Step 2: Calculate the number of moles (n) corresponding to 150. g of ethanol

The molar mass of ethanol is 46.07 g/mol.

150. g × 1 mol/46.07 g = 3.26 mol

Step 3: Calculate the number of molecules in 3.26 moles of ethanol

To convert moles into molecules, we need Avogadro's number: there are 6.02 × 10²³ molecules in 1  mole of molecules.

3.26 mol × 6.02 × 10²³ molecules/1  mol = 1.96 × 10²⁴ molecules

Answer:

(b) fully filled valence s orbitals

Explanation:

Electron configuration of Be: 1s22s2

2s2 is fully filled

Answer:

the original substances in any chemical reaction. products. the resulting substances in any....chromium(III) oxide, and water. (NH4)2Cr2O7(s) → N2(g) + Cr2O3(s) + 4H2O(g).

Explanation:

Chemistry is overall a very interesting subject and it really depends on what you personally consider enjoyable. I love chemistry and I think that grade 11 chemistry is very easy. It's mostly based on balancing chemical equation, molar mass calculations and more. But it's a great course to take based on my experience.

Answer:

1c

2b

3a

Explanation:

Step 1: Write the general expression to calculate the freezing point depression

The freezing point depression is a colligative property, that can be calculated using the following expression.

ΔT = i × Kc × b

where,

i: van 't Hoff factor (number of ion particles per formula unit)

Kc:  cryoscopic constant (Kc for water: 1.86 °C.Kg/mol)

b: molality (moles of solute per kilogram of solvent)

All the solution have the same Kc and the same b (1 mol/1 kg = 1 m), so ΔTf variation will depend on i

Step 2: Calculate the freezing point of the Na₃PO₄ solution

Na₃PO₄ has 4 ions (3 Na⁺ and 1 PO₄³⁻), so i = 4.

ΔT = i × Kc × b = 4 × 1.86 °C.Kg/mol × 1 mol/kg = 7.44 °C

T = 0°C - 7.44 °C = -7.44 °C

Step 3: Calculate the freezing point of the CuSO₄ solution

CuSO₄ has 2 ions (1 Cu²⁺ and 1 SO₄²⁻), so i = 2.

ΔT = i × Kc × b = 2 × 1.86 °C.Kg/mol × 1 mol/kg = 3.72 °C

T = 0°C - 3.72 °C = -3.72 °C

Step 4: Calculate the freezing point of the C₆H₁₂O₆ solution

C₆H₁₂O₆ is a nonelectrolyte (it doesn't ionize), so i = 1

ΔT = i × Kc × b = 1 × 1.86 °C.Kg/mol × 1 mol/kg = 1.86 °C

T = 0°C - 3.72 °C = -1.86 °C

Answer:

What is the question your asking?

Explanation:

All atoms of the same element have the same properties.

Answer:

65.38 u

Explanation:

hope this helps you out!!!!!!!

They Mean D and not U H just took the test and its D i hope this help

Answer:

A. heavy nuclei

Explanation:

They absorb neuyrons in order to hain stability.

Answer:

ako po kailangan ko po nga ayuda

Explanation:

thanks for the points ❤️

Answer:

I think the answer is 2mL.

Explanation:

i hope it help.

Answer: Mass is converted to the energy binding a nucleus together.

Explanation: a p e x

Mass is converted to the energy binding a nucleus together cause a mass defect.Hence , Option (C) is correct.

The actual atomic mass is less than the predicted mass calculated by adding the masses of nucleons.

This additional mass is accounted for by binding energy that is released when a nucleus is formed.

When a nucleus is formed, some of the mass is converted to energy and this results in the mass defect.

Therefore, Mass is converted to the energy binding a nucleus together cause a mass defect. Hence , Option (C) is correct.

Learn more about mass defect here ;

https://brainly.com/question/11624098

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Answer:

Explanation:

\we must convert the mass of NaCl in grams into moles. We do this by dividing by the molecular weight of NaCl (58.4 g/mole). Then, we divide the number of moles by the total solution volume to get concentration. The NaCl solution is a 0.1 M solution.

Answer:

0.125

Explanation:

boom

Answer:

C

Explanation:

energy from different sources leads to different types of rocks. energy inside the earth(volcanoes) melts rocks into liquid rock(molten larva) but energy from the sun(heat radiation) causes rock to weather(breakdown) into small pieces of rocks

Answer:

7.23x10^23 atoms

Explanation:

1 mole = 6.023x10^23

1.20 mole = 6.023x10^23 x 1.2

                = 7.23x10^23 atoms

The atoms present in 1.20 moles of copper is 7.23 × [tex]10^{23}[/tex] atoms.

A chemical element is made up of atoms, which are the basic components of ordinary matter.

Calculation of atoms

Given data:

n = 1.20 moles.

It is known that.

1 mole = 6.023 × [tex]10^{23}[/tex]

So, 1.20 moles = 6.023 ×  [tex]10^{23}[/tex]  × 1.2 = 7.23 ×  [tex]10^{23}[/tex]  atoms.

Therefore, number of atoms in copper will be  7.23 ×  [tex]10^{23}[/tex] atoms.

To know more about atom click here.

https://brainly.com/question/1566330

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Answer:

The correct answer is - 2770000 cm.

Explanation:

1 kilometer = 1000 meter

1 meter = 100 centimeter

1 kilometer = 100*1000 cm

1 km = 100000 cm.

then,

27.7 kilometers = 2.77 × 10^6 centimeters

So, 27.7 kilometers = 27.7 × 100000

= 2.77 × 106 or 2770000 centimeters.

Answer:

the frequency of photons [tex]v = 1.509\times10^{39}Hz[/tex]

Explanation:

Given:  first ionization energy of 1000 kJ/mol.

No. of moles of sulfur = 1 mole

[tex]\Delta E_1 = 1000KJ/mol[/tex]

We know that plank's constant

[tex]h = 6.626\times10^{-34} Js[/tex]

Let the frequency of photons be ν

Also we know that ΔE = hν

this implies ν = ΔE/h

[tex]= \frac{10^6J}{6.626\times10^{-34} Js}[/tex]

[tex]v = 1.509\times10^{39}Hz[/tex]

Hence, the frequency of photons [tex]v = 1.509\times10^{39}Hz[/tex]

[tex] \longrightarrow\sf \pmb {Exothermic \: Reaction}[/tex]

[tex] \tt \green {An \: exothermic \: reaction \: is \: indicated \: by \: writing \: “+Heat” \: or \: “+Heat \: energy” \: or \: “+Energy” \: on \: the \: products \: side \: of \: an \: equation.}[/tex]

Answer: Heat is included as one of the products.

Explanation:

Answer:

18.6 ml

Explanation:

From the balanced equation given:

Volume of oxygen = 27.9 mL

From the equation, we will see that three moles of oxygen react with CS_2 to give two moles of sulfur dioxide (SO_2)

Also, three mL of O_2 yields two mL of SO_2

Now, to calculate the volume of SO_2; we have:

[tex]=27.9 mL \times \dfrac{2 mL \ of SO_2}{3 mL \ O_2}[/tex]

= 18.6 mL of SO_2

Answer: There are 0.0129 moles of silver present in 1.4 grams of silver (Ag).

Explanation:

Given: Mass of silver = 1.4 g

Number of moles is the mass of substance divided by its molar mass.

As molar mass of silver is 107.86 g/mol. Therefore, moles of silver are calculated as follows.

[tex]No. of moles = \frac{mass}{molar mass}\\= \frac{1.4 g}{107.86 g/mol}\\= 0.0129 mol[/tex]

Thus, we can conclude that there are 0.0129 moles of silver present in 1.4 grams of silver (Ag).