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Answer:

it changes color from blue to light green.

Explanation:

due to copper iron nail functions

Answer:

give the other person brainlieset plz

Explanation:

Answer:

2.5 g mass of Ra-226 will remain after 4800 years.

Explanation:

Given data:

Mass of Ra-226 = 20 g

Sample remain after 4800 years = ?

Solution:

Half life of Ra-226 = 1600 years

Number of half lives passed = T elapsed / half life

Number of half lives passed = 4800 year / 1600 year

Number of half lives passed = 3

At time zero = 20 g

At first half life = 20 g/2 = 10 g

At 2nd half life = 10 g/2 = 5 g

At 3rd half life = 5 g/2 = 2.5 g

Thus, 2.5 g mass of Ra-226 will remain after 4800 years.

Answer:

Periodic tables can use color to identify other element characteristics. For example, an electronegativity periodic table color codes the elements based on how electronegative they are. The valence periodic table uses color to identify the most common valence state for each element.Oct 2, 2019

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The color given to a the elements in periodic table is to characteristics of the elements mainly to identify whether they are solid, gas or liquid. Thus option D is correct.

A periodic table contains all the discovered elements which are classified into different groups and periods. Groups are vertical columns of elements with similar properties and same number of valence electrons.

Periods are horizontal rows from left to right with an increase in atomic number. There are 18 groups and 7 periods in periodic table. Each group has given each color and some elements showing exceptional characteristics such as hydrogen and helium have separate colors.

All the first group elements called alkali metals have one color and the second groups elements with another color, All the d-block elements are given the same colour and metals in p-block elements have the same color.

Similarly, all the metalloids have one color and all other gases have the same colour in which inert gas group and halogen group have seperate colours.

Hence, the color in periodic table helps to identify the element's nature like its state also. Thus option D is correct.

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Answer:

what r the options??????

Mole measure the number of elementary entities of a given substance that are present in a given sample. To find mass of 2.25 mol of the element Iron (Fe), we multiply 2.25 mol by (55.84g divided by 1 mol). Therefore option c is correct option.

The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance.

Mathematically,

Mole of Fe element=  mass of Fe element÷ Molar mass of Fe element

mass= Mole of Fe element ×Molar mass of Fe element

Substituting the given values in above formula we get

mass= 2.25 mol× 55.84 g/mole

mass= 2.25 mol× 55.84 g/mole

To find mass of 2.25 mol of the element Iron (Fe), we multiply 2.25 mol by (55.84g divided by 1 mol).

Therefore option c is correct option.

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Answer:

reverse osmosis

Explanation:

Water treatment is often complicated because it deals with the chemical makeup of the water, which varies widely. The first step is to determine what contaminants should be removed. Unfortunately, this is not always a straightforward process. Many contaminants make themselves known in obvious ways, such as iron or hydrogen sulfide, which can cause taste and odor issues. Other contaminants, such as arsenic or pesticides, are only uncovered through a sophisticated laboratory analysis.

It is important to test the water so that the right type of treatment system can be selected. Keep in mind, however, that more than one analysis may be necessary to get a baseline because water quality fluctuates. More information on possible contaminants in a specific area can be obtained by talking to residents, the local health department, the water department, or the state geological society. In addition, your laboratory should be able to recommend appropriate tests based on a customer’s concerns and the information provided about the water source. It is important not only to address customers’ concerns but also to educate them about potential contaminants they may not have considered.

Answer:

❤C. A liquad becomes a solid❤

Explanation:

✌When you freeze water its a scientific fact that it becomes solid.✌

Answer: They are all odorless, colorless, monatomic gases with very low chemical reactivity.

Explanation: Plz give brainliest

Answer:

1.8069*10²⁴molecules of CO₂ and H₂O are produced.

Explanation:

C₃H₅OH + O₂ → CO₂ + H₂O

The law of conservation of matter states that since no atom can be created or destroyed in a chemical reaction, the number of atoms that are present in the reagents has to be equal to the number of atoms present in the products.

Then, you must balance the chemical equation. For that, you must first look at the subscripts next to each atom to find the number of atoms in the equation. If the same atom appears in more than one molecule, you must add its amounts

Left side: 3 C, 6 H and 3 O.

Right side: 1 C, 2 H and 3 O.

The coefficients located in front of each molecule indicate the amount of each molecule for the reaction. This coefficient can be modified to balance the equation, just as you should never alter the subscripts.

By multiplying the coefficient mentioned by the subscript, you get the amount of each element present in the reaction.  

So, balancing the C:

C₃H₅OH + O₂ → 3 CO₂ + H₂O

Then:

Left side: 3 C, 6 H and 3 O.

Right side: 3 C, 2 H and 7 O.

Now, balancing the H:

C₃H₅OH + O₂ → 3 CO₂ + 3 H₂O

Then:

Left side: 3 C, 6 H and 3 O.

Right side: 3 C, 6 H and 9 O.

Finally, balancing the O:

C₃H₅OH + 4 O₂ → 3 CO₂ + 3 H₂O

Then:

Left side: 3 C, 6 H and 9 O.

Right side: 3 C, 6 H and 9 O.

Since you have the same amount of each element on each side of the reaction, the reaction is balanced. Then 3 moles of CO₂ and 3 moles of H₂O are produced.

Avogadro's Number or Avogadro's Constant is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023*10²³ particles per mole and it applies to any substance.

Then the following rule of three applies: if 1 mole contains 6.023*10²³ molecules, then 3 moles of CO₂ or 3 moles of H₂O, how many molecules does it contain?

[tex]amount of molecules=\frac{3 moles* 6.023*10^{23} molecules}{1 mole}[/tex]

amount of molecules= 1.8069*10²⁴

1.8069*10²⁴ molecules of CO₂ and H₂O are produced.

Answer:

Sodium

because it burns with a yellow-orange flame.

Explanation:

It relates with Barium which burns with yellowish green flame

Answer:

Explanation:

the vector sum of all such forces which equals zero for an object at rest. CASE 1: Considering a basketball of weight 1kg, if it has been kept stationary on the ground, there are two forces acting on it. These are it's weight (gravity) and equal and opposite force from the ground (normal reaction).

Answer:

The net force is zero. :)

Explanation:

Answer:

yuh 100% true dude

Explanation:

...............

Answer:

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula

[tex]n = \frac{N}{L} \\[/tex]

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question we have

[tex]n = \frac{9.20 \times {10}^{24} }{6.02 \times {10}^{23} } \\ = 15.282392..[/tex]

We have the final answer as

Hope this helps you

Answer:

Nice! If only....

Explanation:

Answer:

omg lol what even is this

Answer:

[tex]Mass = 102g[/tex]

Explanation:

Given

Compound: [tex]Al_2O_3[/tex]

Required

Determine the equivalent mass

In the above compound, we have: 2 Al and 3 (O)

The atomic mass of Aluminium is:

[tex]Al = 27[/tex]

The atomic mass of Oxygen is:

[tex](O) = 16[/tex]

So, the equivalent mass is:

[tex]Mass = 2 * 27 + 3 * 16[/tex]

[tex]Mass = 54 + 48[/tex]

[tex]Mass = 102g[/tex]

Answer:

35.50

Explanation:

There are two stable isotopes, 35Cl (75.77%) and 37Cl (24.23%), giving chlorine a standard atomic weight of 35.45

Answer: transcribing information to the dna sequence for use by the cell

Explanation:

Answer:

B. Fan

Explanation:

The device in the options which converts electrical energy to kinetic

energy is the Fan.

When the fan is plugged to a an electric power source, the electrical energy gets converted to kinetic energy as a result of the movement of the blades in which Kinetic energy is defined as the energy as a result of the motion of a particle or substance.

Answer:

Combination or synthesis

Explanation:

The given reaction is:

            6Li +  N₂ → 2 Li₃N

This reaction is a synthesis or combination reaction. 6 moles of Li combines with nitrogen gas to produce 2 moles of  Li₃N.

Answer:

Microwaves

Explanation:

Microwaves have more energy than blue light

Among microwaves or blue light, blue light has a higher frequency. This is because blue light belongs to the visible region has a short wavelength and produces a higher amount of energy.

The frequency of any wave is inversely related to the wavelength. This means that when the frequency of the wave increases, the wavelength decreases. While the relationship between frequency is directly related to the energy.

According to the context of this question, gamma rays have the highest frequency and shorter wavelength, while radiowaves have a shorter frequency and the highest wavelength.

Therefore, blue light has a higher frequency. This is because blue light belongs to the visible region has a short wavelength and produces a higher amount of energy.

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Answer:

d

Explanation:

i think it's d, but I'm not sure. my answer is a little different but maybe i used a different number for the density of lead (11.35g/cc)

Answer:

Free chlorine involves the amount of chlorine that's able to sanitize contaminants, while combined chlorine refers to chlorine that has combined directly with the contaminants. Total chlorine is basically the sum of free chlorine and combined chlorine.

Explanation:

chlorine -35 being chlorine

chlorine -37 being free chlorine

Answer:

Ld₂Mz

General Formulas and Concepts:

Chemistry - Compounds

Explanation:

Step 1: Define

"Lindenium" Ld w/ oxidation charge of +1

"Mendezine" Mz w/ oxidation charge of -2

Step 2: Write Compound

To balance out the charges to be neutral (0), we must counter balance the amount of Ld's with Mz's. We need 2 Ld's with 1 Mz to create a compound with a neutral charge:

2Ld¹⁺ + Mz²⁻

2(+1) + (-2) = (+2) + (-2) = 0 (neutral charge)

Therefore, our compound must be Ld₂Mz.

Answer:

forms of mercury

Explanation:

Answer:

Explanation:

Mercury is an element and a metal that is found in air, water, and soil.Mercury rarely occurs uncombined in nature, but can be found as droplets in cinnabar (mercury sulfide) ores. China and Kyrgyzstan are the main producers of mercury. The metal is obtained by heating cinnabar in a current of air and condensing the vapour.

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