Help me please I’m struggling very bad

Answer:

This is a physical test. A chemical test for starch is to add iodine solution (yellow/brown) and look for a colour change. In the presence of starch, iodine turns a blue/black colour. ... Benedict's reagent will give a positive test result for glucose but not for starch.

Explanation:

please give me brainlist and follow

Answer:Amylose in starch is responsible for the formation of a deep blue color in the presence of iodine. The iodine molecule slips inside of the amylose coil.

Explanation:This makes a linear triiodide ion complex with is soluble that slips into the coil of the starch causing an intense blue-black colo

Answer:

producer

Explanation:

Explanation:

잘 봐 넌 그 꼴 나지

우린 탁 쏴 마치 콜라지

너의 각막 깜짝 놀라지

꽤 꽤 폼나지 포 포 폼나지

Answer:

Hey mate.....

Explanation:

This is ur answer......

While sunlight is the energy source, the greatest force propelling the water cycle is gravity. Gravity is the force of attraction between two objects, and Earth's gravity pulls matter downward, toward its center. It pulls precipitation down from clouds and pulls water downhill. Gravity also moves air and ocean water.

Hope it helps!

mark me brainliest plz.....

Follow me!! :)

Answer:

No, water doesn't burn. It only can burn under specific conditions in a lab.

Explanation:

Answer:

Electromagnet creates electricity.

Explanation:

Answer:

B

Explanation:

Elements in a group are determined by the number of valence electrons

Elements in a period are determined by the number of electrons shell

The electronic configuration of the element is

2,8,8

the number of valence electron is 8 that means it is in Group 8/O

the number of electron shell is 3 that means it is in period (row) 3

Group 8/O elements are called Noble gases

Explanation:

Stop cheating and use your brains kiddos

Answer: D: Global warming focuses only on temperature increasing, climate changes is a broader term that refers to the range of changes happening on Earth in addition to temperature changes

Explanation:

Answer:

what he/she said

Explanation:

Answer:

Objects are NOT accelerating if they are traveling in a straight line at constant speed

Slow it down

Answer:

90% of people marry there 7th grade love. since u have read this, u will be told good news tonight. if u don't pass this on nine comments your worst week starts now this isn't fake. apparently if u copy and paste this on ten comments in the next ten minutes you will have the best day of your life tomorrow. you will either get kissed or asked out in the next 53 minutes someone will say i love u

If 8 moles of magnesium chloride react with enough aluminum then the amount of aluminum chloride produced is 5.3 mole.

Aluminum is defined as a chemical substance with the atomic number 13 and the symbol Al. Aluminum has a density that is around one third that of steel, which is lower than that of most common metals. It has a strong affinity for oxygen, and when exposed to air, creates a protective oxide coating on the surface.

3 moles MgCl2and 2 moles Al will produce 3 moles Mg and 2 moles AlCl3.Therefore, if 8.0 moles of MgCl₂ react, the amount of ammonium chloride that may hypothetically be created can be calculated using the mole ratio between MgCl₂  and AlCl₃ .

8.0 mole MgCl₂ x 2 mole AlCl₃ / 3mol MgCl₂

= 5.3 mole AlCl3

Thus, if 8 moles of magnesium chloride react with enough aluminum then the amount of aluminum chloride produced is 5.3 mole.

To learn more about aluminum, refer to the link below:

https://brainly.com/question/9496279

#SPJ2

Answer: The final pressure is 0.81 kPa

Explanation:

The combined gas equation is,

[tex]\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}[/tex]

where,

[tex]P_1[/tex] = initial pressure of gas = 0.58 kPa

[tex]P_2[/tex] = final pressure of gas = ?

[tex]V_1[/tex] = initial volume of gas = v

[tex]V_2[/tex] = final volume of gas = [tex]v-\frac{40}{100}\times v=0.6v[/tex]

[tex]T_1[/tex] = initial temperature of gas = [tex]25^0C=(25+273)K=298K[/tex]

[tex]T_2[/tex] = final temperature of gas = [tex]-22^0C=(-22+273)K=251K[/tex]

Now put all the given values in the above equation, we get:

[tex]\frac{0.58\times v}{298}=\frac{P_2\times 0.6v}{251}[/tex]

[tex]P_2=0.81kPa[/tex]

The final pressure is 0.81 kPa

Answer:

% Ca = 24.69%

% H = 1.2%

% C = 14.8%

% O = 59.25%

Explanation:

The percentage by mass of each element can be calculated by dividing the mass of each element in the compound by the molar mass of the compound.

Molar mass of Ca(HCO3)2

Where; (Ca= 40, H = 1, O = 16, C= 12)

= 40 + {1 + 12 + 16(3)}2

= 40 + {13 + 48}2

= 40 + {61}2

= 40 + 122

= 162g/mol

- % mass of Ca = 40/162 × 100

= 0.2469 × 100

= 24.69%

- % mass of H = 2/162 × 100

= 0.012 × 100

= 1.2%

- % mass of C = 24/162 × 100

= 0.148 × 100

= 14.8%

- % mass of O = 96/162 × 100

= 0.5925 × 100

= 59.25%

Explanation:

the answer is C marbles hope you find it helpful

Answer: I think the answer is 2.5 M.

Explanation:  Formula: M = n/v

M= 10 mol / 4L

M= 2.5 M

Answer:

C. Precipitation of white bismuth hydroxide.

Explanation:

When aqueous ammonia is added to a solution that has Bi3+ and CU2+ cations, what we would have as a chemical result is the precipitation of white Bismuth hydroxide.

The chemical reaction for this can be written as,

Bi3+ + 2NH3 + 3H2O ⇌ Bi(OH)3(s) + 3NH4

Thank you!

Answer:

The water cycle shows the continuous movement of water within the Earth and atmosphere. It is a complex system that includes many different processes. Liquid water evaporates into water vapor, condenses to form clouds, and precipitates back to earth in the form of rain and snow. Water in different phases moves through the atmosphere (transportation). Liquid water flows across land (runoff), into the ground (infiltration and percolation), and through the ground (groundwater). Groundwater moves into plants (plant uptake) and evaporates from plants into the atmosphere (transpiration). Solid ice and snow can turn directly into gas (sublimation). The opposite can also take place when water vapor becomes solid (deposition).

Answer: yes

Explanation:

Answer:

116 g

Explanation:

From the question given above, the following data were obtained:

Number of mole of calcium = 2.9 moles

Mass of calcium =.?

The mole and mass of a substance are related according to the following formula:

Mole = mass / molar mass

With the above formula, we can obtain the mass of calcium. This can be obtained as follow:

Number of mole of calcium = 2.9 moles

Molar mass of calcium = 40 g/mol

Mass of calcium =.?

Mole = mass / molar mass

2.9 = mass of calcium / 40

Cross multiply

Mass of calcium = 2.9 × 40

Mass of calcium = 116 g

Therefore, the mass of 2.9 moles of calcium is 116 g.

Answer:

here you go

Explanation:

The reaction of phenol with bromine is known as bromination of phenol. Solvent has great influence on the reaction. In different solvents, different products are obtained. The action of bromine on phenol can be explained as:

Reaction with bromine in water:—-

Reaction with bromine in water

Phenol reacts with bromine water to give 2,4,6-tribromophenol.

In water, ionisation is facilitated. Phenol gets ionised to form phenoxide ion, which is even better ortho,para-directing. Bromine also gets ionised to a larger extent to form a large number of bromonium ions. And Bromine ions are highly stabilized in ionic solvents. So the formation of strong o,p-directing group and stabilization of Br+ enhances the formation of tribromophenol.

Reaction with bromine in CS2:—-

Reaction with bromine in non-polar organic solvents

Phenol reacts with bromine in a presence of Carbon disulphide to form a mixture of o-bromophenol and p-bromophenol. Among which p-bromophenol predominates. In CS2 ionisation is not facilitated that much. As it is a non-polar solvent it doesn't the Br+ on. Also −OH group is moderately o,p-directing. So as usual para-product is more formed.

Answer:

6

Explanation:

FCC is face centered cubic lattice. In FCC structure, there are eight atoms at the eight corner of the cubic unit cell and one atom centered in each of the faces. FCC unit cells consist of four atoms, (8/8) at the corners and (6/2) in the faces.

Given that, Cu has FCC structure and it contains a vacancy at origin (0, 0, 0). And there is no other vacancy directly adjacent to the vacancy at the origin. So, all the adjacent positions contain Cu atoms. Hence, the total number of adjacent atoms of the vacancy at origin can jump into this vacancy.

the above FCC unit cell clearly indicates that there are six adjacent atoms adjacent to the vacancy at origin

So, the total number of adjacent atoms of the vacancy at origin can jump into this vacancy is 6.

Answer:

The possible source of errors as regard the Procedure are:

Explanation:

The procedure referred to should a experiment with regards heat

The possible source of errors as regards the Procedure are:

Answer:

The amount of water vapor in air influence density. Water vapor is relatively light compared to diatomic Oxygen and diatomic Nitrogen - the dominant components in air. When vapor content increases in moist air the amount of Oxygen and Nitrogen are decreased per unit volume and the density of the mix decreases since the mass is decreasing.

Explanation:

Answer:

Ground Wires

Explanation:

Answer:

45g

Explanation:

Use the Mole = Mass x Mr equation:

Rearrange the above equation to find mass,

Mass = 2.5 moles x 18 (Mr of H₂O) = 45g

Therefore answer is 45g

Answer:

Given

number of moles (n) =2 . 5 mol

R.tc maas of H2O (m) =?

sln

H2O =(1x2+16)

=18g/mol

n=m/mr

m=nxmr

m=2.5x18

m=45g

mass of water is 45g

Answer:

yellow goes under...... for example.