When you test starch with Barfoed’s reagent, what would be the answer, positive or negative?

Answer:

Subject of the experiment and out of scope

Explanation:

In any research study, the process of thing studied is basically the subject of the experiment on which research is conducted to determine the outcomes. If any thing lies out of the experimental process reach, then it is said to be out of scope of the experiment.

Answer:

TRUE ,hope it helped you

Explanation:

Answer:

me too

Explanation:

Answer:

Explanation:

Hope it helps ^-^

#CarryOnLearning

Answer:

When an atom has an equal number of electrons and protons, it has an equal number of negative electric charges (the electrons) and positive electric charges (the protons). The total electric charge of the atom is therefore zero and the atom is said to be neutral. ... Chemically, we say that the atoms have formed bonds

Answer:

[tex]\mathbf{FeCl_3 + AgNO_3 \to 3 AgCl+Fe(NO_3)_3}[/tex]

Explanation:

From the given question,

The chemical equation is:

[tex]\mathbf{FeCl_3 + AgNO_3 \to 3 AgCl+Fe(NO_3)_3}[/tex]

We are given that:

mass of [tex]FeCl_3[/tex] = 45 g

number of moles of [tex]FeCl_3[/tex]  = 45 g/162.2 g/mol

= 0.28 mol

mass of [tex]AgNO_3[/tex] = 25g

number of moles of [tex]AgNO_3[/tex]  = 25/169.87

= 0.147 mol

From the given equation 1 mole of [tex]FeCl_3[/tex] is required to make 3 mole of [tex]AgNO_3[/tex]  

0.28 mole of [tex]FeCl_3[/tex] = 0.28 × 3 = 0.84 mol of [tex]AgNO_3[/tex]  

Here [tex]AgNO_3[/tex]  is the limiting reagent.

Thus,

3 mole of [tex]AgNO_3[/tex]  = 3 moles of AgCl

0.147 mole of [tex]AgNO_3[/tex] = 0.147 mole of AgCl produced.

Answer:

The right approach is "80 g".

Explanation:

Given:

[tex]L_f=80 \ Cal/g[/tex]

[tex]L_v=540 \ Cal/g[/tex]

[tex]S=1 \ Cal/g[/tex]

Now,

The amount of heat cooling will be:

= [tex]mL_v+mS \Delta T[/tex]

= [tex](10\times 540)+10\times 1\times (100-0)[/tex]

= [tex]5400+1000[/tex]

= [tex]6400 \ Cal[/tex]

then,

⇒ [tex]m_{ice} L_f=6400[/tex]

[tex]m_{ice}\times 80=6400[/tex]

        [tex]m_{ice}=\frac{6400}{80}[/tex]

                [tex]=80 \ g[/tex]            

Answer:

93.4 mL

Explanation:

Let's state the reaction:

2AgNO₃ +  Na₂CO₃  →   Ag₂CO₃  +  2NaNO₃

We determine the moles of sodium carbonate:

0.3572 g . 1mol / 105.98g = 3.37×10⁻³ moles

Ratio is 1:2. We say:

1 mol of sodium carbonate react to 2 moles of silver nitrate

Then, our 3.37×10⁻³ moles of carbonate may react to: 3.37×10⁻³ . 2

= 6.74×10⁻³ moles

If we convert to mmoles → 6.74×10⁻³ mol . 1000 mmol / mol = 6.74 mmol

Molarity is mol/L but we can use mmol /mL

6.74 mol / volume in mL = 0.07216 M

6.74 mol / 0.07216 M = volume in mL → 93.4 mL

The question is incomplete, the complete question is:

Nitrogen and fluorine react to form nitrogen fluoride according to the chemical equation:

[tex]N_2(g)+3F_2(g)\rightarrow 2NF_3(g)[/tex]

A sample contains 19.3 g of [tex]N_2[/tex] is reacted with 19.3 g of [tex]F_2[/tex]. Now we need to find the amount of [tex]NF_3[/tex] that can be formed by the complete reactions of each of the reactants.

If all of the [tex]N_2[/tex] was used up in the reaction, how many moles of [tex]NF_3[/tex] would be produced?

Answer: 1.378 moles of [tex]NF_3[/tex] are produced in the reaction.

Explanation:

The number of moles is defined as the ratio of the mass of a substance to its molar mass.

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]       ......(1)

Limiting reagent is defined as the reagent which is completely consumed in the reaction and limits the formation of the product.

Excess reagent is defined as the reagent which is left behind after the completion of the reaction.

In the given chemical reaction, [tex]N_2[/tex] is considered as a limiting reagent because it limits the formation of the product and it was completely consumed in the reaction.

We are given:

Mass of [tex]N_2[/tex] = 19.3 g

Molar mass of [tex]N_2[/tex] = 28.02 g/mol

Putting values in equation 1:

[tex]\text{Moles of }N_2=\frac{19.3g}{28.02g/mol}=0.689mol[/tex]

For the given chemical reaction:

[tex]N_2(g)+3F_2(g)\rightarrow 2NF_3(g)[/tex]

By the stoichiometry of the reaction:

1 mole of [tex]N_2[/tex] produces 2 moles of [tex]NF_3[/tex]

So, 0.689 moles of [tex]N_2[/tex] will produce = [tex]\frac{2}{1}\times 0.689=1.378mol[/tex] of [tex]NF_3[/tex]

Hence, 1.378 moles of [tex]NF_3[/tex] are produced in the reaction.

Answer:

a. 0.4539g benozic acid

b. 60.29% of benzoic acid in the solid sample

Explanation:

The benzoic acid reacts with NaOH as follows:

C6H5COOH + NaOH → C6H5COONa + H2O

Where 1 mole of the acid reacts per mole of NaOH

The NaCl doesn't react with NaOH

To solve this question we must find the moles of NaOH added = Moles of benzoic acid. With the moles of the acid and its molar mass (C6H5COOH = 122.12g/mol) we can find the mass of the acid and its mass percentage:

a. Moles NaOH = Moles Benzoic acid:

24.78mL = 0.02478L * (0.150mol / L) = 0.003717 moles Benozic acid

Mass benzoic acid:

0.003717 moles Benozic acid * (122.12g / mol) = 0.4539g benozic acid

b. Mass percentage is:

0.4539g / 0.7529g * 100 = 60.29% of benzoic acid in the solid sample

Answer:

Q = 669.44 J

Explanation:

Given that,

Mass of water, m = 32 g

The temperature change from 25.0°C to 20.0°C.

We need to find the amount of heat energy transferred. Let it is Q. We know that,

[tex]Q=mc\Delta T[/tex]

Where

c is the specific heat of water

Put all the values,

[tex]Q=32\times 4.184 \times (20-25)\\Q=669.44\ J[/tex]

So, 669.44 J of heat energy is transferred from the water.

Answer:

The molecular formula of the compound is C10H16O.

Explanation:

Based on the given information, the mass of an unknown compound is 152 mg or 0.152 g, which was dissolved to produce 75 ml of solution.

The osmotic pressure of the solution is 0.328 atm at 27 degrees C or 300 K.

The formula of osmotic pressure is,

P = CRT

Now putting the values in the formula we get,

0.328 = C*0.0821*300

C = 0.013317

C = (mass/molecular mass) * (1000/volume of solution in ml)

0.013317 = (0.152/Molecular mass) * (1000/75)

Molecular mass = 152.186

C mass = 152.186 * 0.789 = 120.07 grams

C mole = 120.07/12 = 10

H mass = 152.186 * 0.1059 = 16.11 grams

H mole = 16.11/1 = 16

O mass = 152.186 - 120.07 - 16.116 = 16 grams

O mole = 16/16 = 1

Thus, the molecular formula of the compound will be,

C10H16O

The group corresponding to alkali metal, alkali earth metal, halogen, and noble gas is IA,IIA, 17, 18 group respectively.

Learn more about alkali metals at:

brainly.com/question/18153051

#SPJ1

Answer:

1) donate an H+ ion

Explanation:

option 1 is correct

Answer:

571.81 mL

Explanation:

Assuming constant pressure, we can solve this problem by using Charles' law, which states that at constant pressure:

Where in this case:

We input the data:

And solve for V₂:

The new volume would be 571.81 mL.

AAnswer:

Explanation:

Answer: A Molecular Approach, 2/e. Mole ratio. 2 mol C4H10 : 13 mol O2 : 8 mol CO2 : 10 mol H2O. ❖ 2 molecules of C4H10 react ... of aluminum and 73.15 g of sulfur are combined to form aluminum sulfide according to the equation:.

Explanation:

The question is incomplete, the complete question is;

Which produces the greatest number of ions when one mole dissolves in water? a. NaCl b. NH4Cl c. NH4NO3 d. Na2SO4

Answer:

Na2SO4

Explanation:

If we consider the compounds listed in the options one after the other;

NaCl produces two moles of ions in solution

NH4Cl produces two moles of ions in solution

NH4NO3  produces two moles of ions in solution

Na2SO4 produces three moles of ions in solution

We can see that Na2SO4 produces the greatest number of ions when one mole of the substance  is dissolved in water, hence the answer above.

Answer:

2 moles!

Explanation:

Hi i hope this helped! I researched it and 2 moles was what came up first.

Answer: The Answer would be C

Explanation: A spectrum is a Range of Wavelengths and Frequencies of Electromagnetic Radition.

The statement that describe spectrum is a range of wavelengths or frequencies of electromagnetic radiation.

Spectrum arrangement or electromagnetic radiations base on their wavelength and frequency which can be visible light, ultraviolet, and infrared light. An instrument that is use for visual observation of spectra is called a spectroscope.

Therefore, The statement that describe spectrum is a range of wavelengths or frequencies of electromagnetic

radiation.

Learn more about spectrum from the link below.

https://brainly.com/question/4901067

Answer:

0.616 moles of Fe₂(CO₃)₃ are produced when 200 g of FeCl₃ react

b. 1.

Explanation:

The balanced reaction is:

First we convert 200 grams of FeCl₃ into moles, using its molar mass:

Then we convert 1.23 moles of FeCl₃ into moles of Fe₂(CO₃)₃, using the stoichiometric coefficients of the balanced reaction:

The closest answer would be option b. 1.

Explanation:

[tex]FeCl₃ + (NH₄)₂CO₃ → NH₄Cl + Fe₂(CO₃)₃[/tex]

first balance the chemical equation

[tex]2FeCl₃ + 3(NH₄)₂CO₃ → 6NH₄Cl + Fe₂(CO₃)₃[/tex]

2 mole. 3 mole. 6mole. 1mole

2*162g of FeCl₃ produce 236 g of Fe₂(CO₃)₃

200g of of FeCl₃

produce 236/(2*162)*20=145.68 g of Fe₂(CO₃)₃

1 mole of Fe₂(CO₃)₃=236g

145.68g of Fe₂(CO₃)=1/236*145.68=}0.61mole

closest answer is b 1

b.1mole(s) of iron (III) carbonate [Fe2CO3)3] is/are produced in the balanced equation

Answer:

A glacier is a large mass of snow and ice that has accumulated over many years and is present year-round. In the United States, glaciers can be found in the Rocky Mountains, the Sierra Nevada, the Cascades, and throughout Alaska. A glacier flows naturally like a river, only much more slowly. At higher elevations, glaciers accumulate snow, which eventually becomes compressed into ice. At lower elevations, the “river” of ice naturally loses mass because of melting and ice breaking off and floating away (iceberg calving) if the glacier ends in a lake or the ocean. When melting and calving are exactly balanced by new snow accumulation, a glacier is in equilibrium and its mass will neither increase nor decrease.

In many areas, glaciers provide communities and ecosystems with a reliable source of streamflow and drinking water, particularly in times of extended drought and late in the summer, when seasonal snowpack has melted away. Freshwater runoff from glaciers also influences ocean ecosystems. Glaciers are important as an indicator of climate change because physical changes in glaciers whether they are growing or shrinking, advancing or receding provide visible evidence of changes in temperature and precipitation. If glaciers lose more ice than they can accumulate through new snowfall, they ultimately add more water to the oceans, leading to a rise in sea level (see the Sea Level indicator). The same kinds of changes occur on a much larger scale within the giant ice sheets that cover Greenland and Antarctica, potentially leading to even bigger implications for sea level. Small glaciers tend to respond more quickly to climate change than the giant ice sheets. Altogether, the world’s small glaciers are adding roughly the same amount of water to the oceans per year as the ice sheets of Greenland and Antarctica combined. During the last two decades, they added more water overall to the oceans than the ice sheets did.

Explanation:

please give this answer as brainliest answer

Because they offer a variety of essential functions, including as controlling river flows and water supply, safeguarding coastal areas from floods, and preserving biodiversity, glaciers are a crucial component of human survival.

First, many people throughout the world rely heavily on glaciers as a supply of freshwater. When glaciers melt, they release water that has been stored and is subsequently utilised for agriculture, drinking water, and other things.

In dry areas with limited access to other freshwater sources, this water is very crucial. As a natural reservoir, glaciers may also hold a lot of water during the winter and release it gradually throughout the summer. This helps to control river flows and avoid flooding.

Second, glaciers contribute significantly to the global climate.system of climate. Large volumes of carbon dioxide and other greenhouse gases are released as glaciers melt, which can contribute to global warming. Glaciers may also reflect sunlight, which aids in cooling the surroundings around them.

High-altitude places, where glaciers can help regulate temperatures and avert catastrophic weather occurrences, are particularly crucial for this cooling impact. Last but not least, glaciers are crucial for the preservation of biodiversity. Numerous types of plants, animals, and microorganisms find a special niche in glaciers. These species may be disrupted by glacier melting, which might result in the extinction of entire ecosystems. The environment and the communities who rely on it may be significantly impacted by this.

Learn more about  Climate models at:

https://brainly.com/question/31171080

#SPJ2

Answer:

The correct answer is 1.21 L.

Explanation:

Based on the given information, the reaction will be,

CS2 (l) + 3Cl2 (g) ⇒ CCl4 (l) + S2Cl2 (l)

By using the standard values of the substances, the standard enthalpy of the reaction is,

ΔH° = [(-139.5) + (-58.5) – 0 – (87.3)] kJ/mol

= -285.3 kJ/mol

The amount of heat evolved for 3 moles of chlorine reacted us 285.3 kJ.

Now the number of moles of chlorine needed to react to produce 5.00 kJ is,

= 5.00 kJ × 3 mol Cl2/285.3 kJ

= 0.0526 mol Cl2

Now the volume of chlorine gas at 27degree C and 812 mmHg will be,

Volume = 0.0526 mol Cl2 × 0.0821 Latm/mol K × 300 K/ 1.07 atm

= 1.21 L

Answer:first part is A and C, second part is C, third part is 40 m/s and the fourth part is zero

Explanation: I guessed and got them right lol

Answer:

Pure water contains no ions.  TRUE

Pure water contains equal amounts of hydroxide [OH-] and hydronium [H3O+ ] ions.  TRUE

Explanation:

This is the equilibrium for pure water:

2H₂O  ⇄  H₃O⁺  +  OH⁻          Kw

We see that pure water has no Ions. Pure water can not conduct electricity.

Generally ionized water comes from the water tap.

Another feature of pure water is pH.

Definetely pH of pure water is : 7

As pH = 7, [H₃O⁺] = 1×10⁻⁷

Then, [OH⁻] = 1×10⁻⁷

This is reazonable because Kw is 1×10⁻¹⁴ and Kw = [H₃O⁺] . [OH⁻]

In conclussion:

Pure water contains no ions.  TRUE

Pure water contains equal amounts of hydroxide [OH-] and hydronium [H3O+ ] ions.  TRUE

Pure water contains larger amounts of hydroxide [OH-] than hydronium [H3O+] ions.  FALSE

Pure water is an electrolyte. FALSE

Pure water contains smaller amounts of hydroxide [OH-] than hydronium [H3O ] ions. FALSE

When the concentration of the HCl is varied, the color of the solution is changed as the equilibrium position moves to the left or right.

The term equilibrium in a chemical reaction connotes that the forward and the revers reactions proceed at the same rate. Let us note that Co(H2O)6^2+ is pink in color while  CoCl4^2– is blue in color.

As such, when the concentration of the HCl is varied, the color of the solution is changed as the equilibrium position moves to the left or right.

Learn more anout equilibrium: https://brainly.com/question/365923

Answer:

XeF4                  True

[PdCl4]2−           True

naphthalene      True

Furan                  False

C4H4O               False  

Explanation:

From the given information:

Only XeF4;  [PdCl4]2−;  naphthalene are true. This is because their molecules contain -nC₂ axis which is perpendicular to the Cn axis. The image attached below shows the structural formula of each compound, there below, we can see that Furan only possesses one C₂ axis but not -nC₂ ⊥ C₂.

We know that [OH⁻] * [H⁺] = 10⁻¹⁴

plugging the value of [H⁺]

[OH⁻] * 1.2 * 10⁻³ = 10⁻¹⁴

[OH⁻] = 10⁻¹⁴ * (10³/1.2)

[OH⁻] = 833.3 * 10⁻¹⁴

[OH⁻] = 8.33 * 10⁻¹²

Answer:

The answer is "the electron configuration of the element".

Explanation:

Electronics are distributed in atomic and molecular orbit via electrons from an atom or a molecule.

It reflects a most frequent dependence on valence electrons in the outer.

Through analyzing the context of the regular periodic table, the individual atoms are helpful. That's also important to understand chemical connections, which hold electrons together. This similar approach helps to explain the specific characteristics of lasers or semiconductors for bulk materials.