3. A gram food sample is burned completely in a calorimeter that contains 1000. of water The temperature of the water increases 23.65 degrees * C . How many Calories does the food have per gram ?

Moles of aluminum produced = 0.588

Given

30 g of Al2O3

Reaction

2Al203 ⇒ 4Al + 302

Required

moles of aluminum

Solution

mol Al2O3 :

= mass : MW

= 30 : 101,96 g/mol

= 0.294

From the equation, mol Aluminum :

= 4/2 x mol Al2O3

= 4/2 x 0.294

= 0.588

Answer:

b or c

Explanation:

Answer:

Boiling Water

Explanation:

Boiling water is an example of physical change and not and not a chemical change because the water vapor still has the same molecular structure as liquid water.If the bubbles were caused by the decomposition of a molecule into gas then boiling would be a chemical change.

Answer:

A chemical change results from a chemical reaction, while a physical change is when matter changes forms but not chemical identity. Examples of chemical changes are burning, cooking, rusting, and rotting. Examples of physical changes are boiling, melting, freezing, and shredding

Explanation:

Answer:

a. The formula for tritoborate ion is B₃O₈²⁻

b. The formula of the compound formed will be Fe₂(B₃O₈)₃ and the name will be Iron (iii) tritoborate

Explanation:

The formation of compounds by atoms of elements occurs in accordance with the valencies of the elements. Valency refers to the combining power of an element. For metallic elements, it is usually the number of electrons they can give up or lose while for non-metallic elements, it is the number of electrons they can accept. The valency of an atom of an element is related to its oxidation number. Metals have positive oxidation numbers while non-metals have negative oxidation numbers. Sometimes, two or more atoms combine together and react as a single unit and may carry a positive or negative charge. These are known as a radicals. For example, ammonium ion, NH₄⁺.

In the given question, calcium tritoborate, CaB₃O₈ is formed from the combination of calcium ion and tritoborate ion. Calcium ion carries the charge of +2, therefore, the tritoborate ion must have a charge of -2 in order to form a compound since the overal charge on a compound is zero.

a. let the tritoborate ion be represented by X

Ca = +2, X = ?

+2 + X = 0

X = -2

Thus, the formula for tritoborate ion is B₃O₈²⁻

b. When tritoborate ion combines with iron (iii) ion, Fe³⁺, two moles of Fe³⁺ will be required to react with three moles of B₃O₈²⁻ in order to have a neutral compound. The formula of the compound formed will be: Fe₂(B₃O₈)₃ and the name will be Iron (iii) tritoborate

Answer:

Follows are the solution to the given question:

Explanation:

Dry Soil weight = solid soil weight = [tex]284 \ grams[/tex]

solid soil volume =[tex]205 \ cc[/tex]

saturated mass soil = [tex]361 \ g[/tex]

The weight of the soil after drainage is =[tex]295 \ g[/tex]

Water weight for soil saturation = [tex](361-284) = 77 \ g[/tex]

Water volume required for soil saturation =[tex]\frac{77}{1} = 77 \ cc[/tex]

Sample volume of water: [tex]= \frac{\text{water density}}{\text{water density input}}[/tex]

[tex]= 361- 295 \\\\ = 66 \ cc[/tex]

Soil water retained volume = (draining field weight - dry soil weight)

                                             [tex]= 295 - 284 \\\\ = 11 \ cc.[/tex]

[tex]\text{POROSITY}= \frac{\text{Vehicle volume}}{\text{total volume Soil}}[/tex]

                    [tex]= \frac{77}{(205 + 77)} \\\\= \frac{77}{(282)} \\\\ = 27.30 \%[/tex]

(Its saturated water volume is equal to the volume of voids)

[tex]\text{YIELD SPECIFIC} = \frac{\text{Soil water volume}}{\text{Soil volume total}}[/tex]

                              [tex]= \frac{66}{(205+77)}\\\\= \frac{66}{(282)}\\\\=0.2340\\\\ = 0.23[/tex]

[tex]\text{Specific Retention}= \frac{\text{Volume of soil water}}{\text{Total soil volume}}[/tex]

                            [tex]= \frac{11}{282} \\\\= 0.0390 \\\\ = 0.04[/tex]

1

ammonia: NH3 (one nitrogen)

bleach: NaOCl (zero nitrogen)

Answer:

4.16 g

Explanation:

Volume,  V = 2.90 L

STP mans standard temperature and pressure

T = 273 K

P = 1 atm

Mass = ?

Using the ideal gas equation;

PV = nRT

where R = General gas constant = 0.082 L atm mol-1 K-1

n = PV / RT

n = 1 * 2.90 /  (0.082 * 273)

n = 2.90 / 22.386

n = 0.130 mol

The relationship between moles and mass;

Mass = number of moles * Molar mass

Mass = 0.130 mol * 32 g/mol

Mass = 4.16 g

Answer:4.14

Explanation:just answered the question

Answer:

68.1% is percent yield of the reaction

Explanation:

The reaction of methane with oxygen is:

CH₄ + 2O₂ → CO₂ + 2H₂O

Where 2 moles of oxygen react per mole of CH₄

Percent yield is:

Actual yield (28.2g CO₂) / Theoretical yield * 100

To solve this question we need to find theoretical yield finding limiting reactant :

Moles CH₄:

15.1g CH₄ * (1mol / 16.04g) = 0.9414 moles

Moles O₂:

81.2g * (1mol / 32g) = 2.54 moles

For a complete reaction of 0.9414 moles of CH₄ are needed:

0.9414 moles CH₄ * (2 mol O₂ / 1mol CH₄) = 1.88 moles of O₂. As there are 2.54 moles, O₂ is in excess and CH₄ is limiting reactant

In theoretical yield, the moles of methane added = Moles of CO₂ produced. That is 0.9414 moles CO₂. In grams = Theoretical yield:

0.9414 moles CO₂ * (44.01g / mol) = 41.43g CO₂

Percent yield: 28.2g CO₂ / 41.43g CO₂ * 100=

Answer:

different chemical properties and the same physical properties

Explanation:

Both carbon monoxide and carbon dioxide are gases.

So physically, the two compounds have no fixed shape and volume and their molecules are far apart.

Therefore, they have similar physical properties.

Based on chemical properties, the compounds or molecules given are different.

They will combine chemically in diverse ways.

3. different chemical properties and the same physical properties

Physical properties:  

Chemical properties:

Therefore, option 3 is correct.

Learn more:

brainly.com/question/15821287

Answer:

118.61 mL.

Explanation:

Hello!

In this case, since we know the concentration in the medication:

[tex]\frac{350.0\mu g}{1mL}[/tex]

Now, since there are 0.50 mg of the medication per kilogram of patient, we can compute the volume as shown below for a 183-lb patient:

[tex]183lb*\frac{1kg}{2.204lb}* \frac{0.50mg}{1kg} *\frac{1000\mu g}{1mg} *\frac{1mL}{350.0\mu g} =118.61mL[/tex]

Best regards!

Answer:

When hydrogen is passed over hot ferric oxide (FeO) hydrogen reacts with oxygen present in the compound and forms water (H2O) and pure Iron

Explanation:

Answer:When hydrogen gas is passed over hot copper oxide, the black coating on the surface turns brown as the reverse reaction takes place and copper is obtained.

Explanation:

Answer:

Krypton

Explanation:

Answer:

Carboxylic acid

Explanation:

Asprin is a drug that contains the carboxylic acid functional group (R-COOH), ester functional group (R-O-CO-R') and the aromatic group (benzene ring).

When we take in aspirin, it becomes salicylic acid. This metabolite irreversibly inhibits the enzyme cyclooxygenase. Hence the the production of protective prostaglandins is blocked causing inflammation and pain.

Answer:

336.6 grams of CO₂ and 183.6 grams of H₂O are formed from 2.55 moles of propane.

Explanation:

In this case, the balanced reaction is:

C₃H₈ + 5 O₂ → 3 CO₂ + 4 H₂O

By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of reactant and product participate in the reaction:

Being the molar mass of each compound:

Then, by stoichiometry, the following quantities of mass participate in the reaction:

So you can apply the following rules of three:

[tex]mass of CO_{2} =\frac{2.55 moles of C_{3} H_{8}*132 gramsof CO_{2} }{ 1 mole of C_{3} H_{8}}[/tex]

mass of CO₂= 336.6 grams

[tex]mass of H_{2}O =\frac{2.55 moles of C_{3} H_{8}*72 gramsof H_{2}O }{ 1 mole of C_{3} H_{8}}[/tex]

mass of H₂O= 183.6 grams

336.6 grams of CO₂ and 183.6 grams of H₂O are formed from 2.55 moles of propane.

Answer:

1.57 × 10^-4

one point five seven times ten to the power of negative four

Answer:

The molar density of any ideal gas at STP is:

1 mol / 22.4 L = 0.04464 mol / L

The molar mass of F2 is: 2(19) = 38 g/mol

0.04464 mol / L * (38 g / mol) = 1.70 g/L

Explanation:

Answer:

the answer is second option. with 2 models

Explanation:

2H2 + O2 gives 2H2O

so there's two models

Answer:

Plants release oxygen in the process of Photosynthesis

Explanation:

Answer:

1 molecule of H2O contains 10 electrons. So one mole that is equal to 22.4 L of H2O will contain 6.022 × 10^23 × 10 electrons. So 1.8 ml will have - 6.022×10^23×1.8×10/22.4 ×1000=6.022×10^21×1.8/22.4.

Explanation:

I just saw this answer here in brainly

Answer: Convergent Boundary

Explanation:

Two plates converge at one point

Answer:

Oxygen and glucose

Explanation:

Plants use the sun, water, and CO2 to make their own energy. Glucose is the result, and Oxygen is just a biproduct.

Answer:

Explanation:

1 mol of sodium = 23 grams (use the number on your periodic table).

0.7350 mol sodium = x

Cross multiply

1*x = 0.7350 * 23

x = 16.905

You will get slightly less than this, depending on your periodic table. But the method will be the same.

Answer:

There was an improvement in accuracy. There was no change in precision.

Explanation:

The average mass after recalibration is closer to the mass of the standard, so the recalibration improved the accuracy (the measurement is closer to an accepted 'true' value).

The standard deviation did not change, so the precision (or how disperse the measurements are) was not affected.

Answer: See explanation

Explanation:

Here's the correct question:

The total ages of 5 children born at the intervals of 3 years each is 50 years. Find the age of the youngest and the oldest child.

From the information given, we can then make the following assumption with regards to their ages.

First child = y

Second child = y + 3.

Third child = y + 6

Fourth child = y + 9

Fifth child = y + 12

Therefore, y + y+3 + y+6 + y+9 + y+12 = 50

5y + 30 = 50

5y = 50 - 30

5y = 20

y = 20/5

y = 4

Youngest child = 4 years

Oldest child = y + 12 = 4 + 12 = 16 years

Answer:

1 molecule of H2O contains 10 electrons. So one mole that is equal to 22.4 L of H2O will contain 6.022 × 10^23 × 10 electrons. So 1.8 ml will have - 6.022×10^23×1.8×10/22.4 ×1000=6.022×10^21×1.8/22.4

Explanation: