how moles are there in 15 grams of SiO2

Answer:

no sure

Explanation:

Answer:

This is considered a hypothesis because it hasn't been confirmed. It is just a guess.

Explanation:

A hypothesis is a limited explanation of a phenomenon; a scientific theory is an in-depth explanation of the observed phenomenon. Law is a statement about an observed phenomenon or a unifying concept, according to Kennesaw State University. However, Newton's law doesn't explain what gravity is, or how it works.

Answer:

c

Explanation:

A. It is a statement of fact about how nature works instead of an explanation.

B. It provides an explanation for many observations and accepted hypotheses.

C. It describes how to test a possible explanation of one specific relationship.

D. It has not changed over time even though new technology has been developed.

Answer:

no definite shape

Explanation:

Answer:

Liquids have no definite shape (takes the shape of its container) they have a definite volume. Particles are free to move over each other, but are still attracted to each other.

Explanation:

Hope this helps!

Answer:

gas and leqwed

Explanation:

leqwed goes to gas

Answer: evaporation and precipitation

Answer:

45 mL

Explanation:

Tenemos los siguientes datos:

V = 1 L

C = 4,5% v/v

El porcentaje en volumen (%v/v) expresa el volumen de soluto (alcohol en este caso) que hay cada 100 mL de solución. Si la solución tiene una concentración del 4,5% v/v eso quiere decir que hay 4,5 ml de alcohol cada 100 ml de solución, de acuerdo a lo siguiente:

4,5% v/v alcohol = volumen alcohol/ volumen solución x 100 = 4,5 mL alcohol/100 mL solución= 4,5 mL alcohol/0,1 L alcohol

Por lo tanto, al multiplicar por el volumen total de la solución (1 L), obtenemos la cantidad total de alcohol:

4,5 mL alcohol/0,1 L alcohol x 1 L = 45 mL

Answer:

Option B. It is a basic solution.

Explanation:

To know which option is correct, let us calculate the pH of the solution.

First, we shall determine the pOH of the solution. This is illustrated below:

Concentration of Hydroxide ion, [OH¯] = 3.5×10¯⁶

pOH =.?

pOH = –Log [OH¯]

pOH = –Log 3.5×10¯⁶

pOH = 5.5

Finally, we shall determine the pH. This can be obtained as follow:

pOH = 5.5

pH =?

pH + pOH = 14

pH + 5.5 = 14

Collect like terms

pH = 14 – 5.5

pH = 8.5

The pH scale reads as follow:

0 to 6 => Acidic

7 => Neutral

8 to 14 => Basic

Comparing the pH of the solution (i.e 8.5) with the pH scale, we can conclude that the solution is basic because the pH of solution lies between 8 and 14.

Answer:

go for it

Explanation:

Answer:

I would be happy to help

Explanation:

Answer:

Mass of sodium metal is 130.87 gram

Explanation:

The complete reaction is

2 NaN3 --> 2 Na + 3 N2

We know that PV = nRT

n = [tex]\frac{PV}{RT}[/tex]

On substituting the given values, we get

[tex]n = \frac{\frac{99707}{101325}*75 }{0.082 *(273.15 +15)} \\n = 3.02[/tex]moles of N2

Sodium azide's molar mass

3.02 *(2/3) = 2.013 moles

Mass = 2.03 * 65.01 = 130.87 gram

Answer:

The earth is made of chemical

Explanation:

Explanation:

because of the chemical made up with earth

Answer:

C

Explanation:

Answer:  1. F

2. F

3. T

4. F

5. T

6. T

Explanation:

I am not sure i'm sorry if it isn't right

Answer:

25.45 Liters

Explanation:

Using Ideal Gas Law PV = nRT => V = nRT/P

V = (1mole)(0.08206Latm/molK)(298K)/(1atm) = 25.45 Liters

Answer: Hopefully this helps! sorry if not. :))

Speed has a greater impact on mass because its increases in velocity have an exponentially greater impact on translational kinetic energy because kinetic energy is proportional to velocity squared. Doubling an object's mass would only double its kinetic energy, however doubling its momentum would quadruple its velocity.

Answer:

d. Solid

Explanation:

It is frozen to be a glacier

Hope this helps :)

Zinc sulphate

Zinc sulphateZnSO₄

This is the answer.

Answer:

2.04moles

Explanation:

The balanced chemical equation of this reaction is given as follows:

Zn + 2HCl → ZnCl2 + H2

Based on the above balanced equation, 2 moles of hydrochloric acid (HCl) reacts to produce 1 mole of Zinc chloride (ZnCl2).

The question states that 148.8 grams HCl reacts. We need to convert this value to mole by using the formula;

mole = mass/molar mass

Molar mass = 36.46g/lol

mole = 148.8/36.46

mole = 4.08moles of HCl

Hence, if 2 moles of hydrochloric acid (HCl) reacts to produce 1 mole of Zinc chloride (ZnCl2).

Then, 4.08moles of HCl will react to produce (4.08 × 1/2)

= 2.04moles of ZnCl2.

Answer:

Carbon has four valence electrons, so it can achieve a full outer energy level by forming four covalent bonds. When it bonds only with hydrogen, it forms compounds called hydrocarbons. Carbon can form single, double, or triple covalent bonds with other carbon atoms.

The carbon-hydrogen bond (C–H bond) is a bond between carbon and hydrogen atoms that can be found in many organic compounds. This bond is a covalent bond meaning that carbon shares its outer valence electrons with up to four hydrogens. This completes both of their outer shells making them stable.

^Hope it helps, Hazel^

Answer:

c

Explanation:

Answer: the place that i put the letters is how it should look also 75% of your peas are green

Explanation:

Answer:

-96.6°C

Explanation:

Given:

        mass CCl4 = 530.0 g * (1 kg / 1000)

        mass CCl4 = 0.5300 kg

First calculate the molality (m) of the solute, which is the moles of solute divided by the kg of solvent ([tex]\frac{moles}{kg}[/tex]):

molality CHCl3 = (mass moles CHCl3) / (mass CCl4 in kg)

molality CHCl3 = (1.31 mol) / (0.5300 kg)

molality CHCl3 = 2.471698m

Decrease in freezing point of solvent = (Kf) * (molality of solute)

Decrease in freezing point of CCl4 = (Kf) * (molality CHCl3)

Decrease in freezing point of CCl4 = (29.8°C/m) * (2.47m)

Decrease in freezing point of CCl4 = 73.6566°C

Then use the molality of the solute to calculate the change in freezing point and subtract the change from the original freezing point.

Freezing point of solution =

(freezing point of pure solvent) - (Decrease in freezing point)

Freezing point of solution = (-22.9°C) - (73.66°C)

Freezing point of solution = -96.6°C

Learn more about freezing point here: brainly.com/question/22888016

The elements that will form covalent bonds are Silicon (Si) and nitrogen (N), option C.

A covalent bond is formed between two atoms by the mutual sharing of one or more pairs of electrons. The two atomic nuclei attract these electrons at the same time. When the difference in electro-negativities of two atoms is too small for electron transfer to form ions, a covalent bond forms.

Hydrogen (H₂) is a molecule with a single covalent bond as well as Halogens like Fluorine (F), Chlorine (Cl), Silicon (Si) and nitrogen (N).

Find out more on covalent bonds here: https://brainly.com/question/12732708

#SPJ1

Answer:

a The molecules of the water in the teacup

hope it helps

Answer: The balanced equation is [tex]AlCl_{3} + 3Cs \rightarrow 3CsCl + Al[/tex]

Explanation:

A chemical equation which contains same number of atoms on both reactant and product side is called a balanced chemical equation.

For example, [tex]AlCl_{3} + Cs \rightarrow CsCl + Al[/tex]

Here, number of atoms on reactant side are as follows.

Number of atoms on product side are as follows.

To balance this equation, multiply Cs by 3 on reactant side and multiply CsCl by 3 on product side.

Hence, now the equation will be as follows.

[tex]AlCl_{3} + 3Cs \rightarrow 3CsCl + Al[/tex]

Here, number of atoms on reactant side are as follows.

Number of atoms on product side are as follows.

Thus, we can conclude that this equation is balanced.

Answer:

5 loaves of bread, 5g of yeast

Answer:

Option D, Index fossil helps scientists to determine the relative ages of rocks by their positions

Explanation:

Index fossils are arranged in layer in such a way that the lowest layer represent the oldest fossil and the top most layer represents the youngest fossil. Scientist use this concept to determine the relative age of the rocks based on their position beneath the earth’s surface

Hence, option D is correct

Answer:

C. Nervous

Explanation:

The nervous system is a system of the body of living organisms which includes the brain, spinal cord and nerves.