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Answer:

Corrosion

Explanation:

Silver is known as a noble metal. Noble metals are those metals that are resistant to corrosion.

However, we can not say that silver is completely resistant to corrosion because silver can corrode when exposed to air and sulphur.

Exposure to air and  sulphur leads to the coating of the silver with a sulphide layer thereby making the metal to become tarnished and loose its metallic luster.

Answer:

v = m/D

Explanation:

Density is defined as the mass per unit volume, or D = m/v. Solve for Density equation for the variable v:

With this we are making v Which represents volume the subject so;

[tex]d = \frac{m}{v} [/tex]

With this you multiply both sides by ;

[tex]v[/tex]

[tex]v(d) = ( \frac{m}{v})v[/tex]

And then the v will multiply the d making it

“vd” and the ‘v’ will cancel the v making it;

[tex]vd = m[/tex]

So then we divide both sides by d to make v the subject.

[tex] \frac{vd}{d} = \frac{m}{d} [/tex]

So the d cancels the d leaving;

[tex]v = \frac{m}{d} [/tex]

Answer:

The best example of direct observation is when the researcher of animal behavior directly observe how animal lives in a reservation.

Answer:

Hi... Your answer is total force

Answer:

im good but mark brainliest

Explanation:

Answer:

i don think thats what she ment

Explanation:

Answer:

28 chromosomes

Explanation:

The elephant egg cells will have just half of the original number of chromosomes which is 28 chromosomes.

The other zygote which is the male sperm will also contain 28 chromosomes.

Answer:

30 I guess

Explanation:

Answer:

too simple question i don't have book pen now otherwise solved it

Answer:

The temperature of a substance in chemistry, is taken as a measure or estimate of the average kinetic energy ([tex]K_{avg}[/tex]) of the atoms or molecules contained in the substance. The 6.02 × 10²³ particles (atoms or molecules) within 1.0 mole of each substance can each posses different amount of kinetic energy at any given time. Some particles move very fast while others move very slow such that the kinetic energy of all the particles are only representable by a distribution and a conclusion regarding the  different aspects of the kinetic energy distribution of the particles of the substances is not easily possible

Explanation:

For a gas, we have;

[tex]KE_{avg} = \dfrac{3}{2} \cdot k \cdot T[/tex]

Where;

[tex]KE_{avg}[/tex] = The average kinetic energy

k = 1.38 × 10⁻²³ J/K

T = The gas temperature in Kelvin

Answer:

C. Trigonal pyramidal

Explanation:

According to the valence shell electron pair repulsion theory, the shape of ammonia is trigonal pyramidal in nature.

The bond angle is 107° and it has bond pair of 3 and lone pair of 1.

A tetrahedral is exhibited by methane

Trigonal planar is exhibited by BF₃

Answer:

The answer is p⁴.

Explanation:

You have to apply Indices Law :

[tex] {a}^{m} \times {a}^{n} ⇒ {a}^{m + n} [/tex]

For this question :

[tex] {p}^{3} \times {p}^{1} [/tex]

[tex] = {p}^{(3 + 1)} [/tex]

[tex] = {p}^{4} [/tex]

Answer:

27.65×10²³ atoms of H

10.37×10²³ atoms of C

Explanation:

Given data:

Mass of C₃H₈ = 25.3 g

Number of hydrogen atom = ?

Number of carbon atom = ?

Solution:

Number of moles of propane:

Number of moles = mass/molar mass

Number of moles = 25.3 g/ 44.1 g/mol

Number of moles = 0.574 mol

1 mole of propane contain 3 mole of carbon atoms.

0.574 moles of propane contain 0.574  × 3 mol = 1.722 moles of C.

1 mole =  6.022 ×10²³ atoms of C

1.722 mole × 6.022 ×10²³ atoms of C / 1 mol

10.37×10²³ atoms of C

Number of atoms of H:

1 mole of propane contain 8 mole of hydrogen.

0.574 moles of propane contain 0.574  × 8 mol = 4.592 moles of H.

1 mole =  6.022 ×10²³ atoms of H

4.592 mole × 6.022 ×10²³ atoms of H / 1 mol

27.65×10²³ atoms of H

Answer:

Synthesis

Explanation:

That's the answer to that question

The pH of a buffer solution : 4.3

Given

0.2 mole HCNO

0.8 mole NaCNO

1 L solution

Required

pH buffer

Solution

Acid buffer solutions consist of weak acids HCNO and their salts NaCNO.

[tex]\tt \displaystyle [H^+]=Ka\times\frac{mole\:weak\:acid}{mole\:salt\times valence}[/tex]

valence according to the amount of salt anion  

Input the value :

[tex]\tt \displaystyle [H^+]=2.10^{-4}\times\frac{0.2}{0.8\times 1}\\\\(H^+]=5\times 10^{-5}\\\\pH=5-log~5\\\\pH=4.3[/tex]

Answer:

560000 cg

Explanation:

5.6 x 10^3 = 5600

1 g = 100 cg

5600 g = 560000 cg

Answer:

Explanation:

"An early link between cancer and a chemical was found in the late 1700s. An English physician noted that a large number of chimney sweeps had cancer of the scrotum due to exposure to soot, which contains chemicals known as polycyclic aromatic hydrocarbons. Since then, many more chemicals have been identified as known or suspected causes of cancer. "

Answer:

Chemical cause cancer

Explanation:

Answer:

CO(g) + H2O(g) ⇌ CO2(g) + H2(g)

Answer:

O ( Oxygen )

because oxygen atom is a non metal and highly electronegative which reacts by itself to form a di-molecular compound of Oxygen

[tex]O _{2}[/tex]

Answer:

A small mass of positive charge was discovered in the center of the atom.

Explanation:

Atoms is the combination of protons, neutrons, as well as electrons particles. The particles that are in the centre of atom is Protons and neutrons, which made up the nucleus, this nucleus is surrounded by electron.

The discovery that directly caused scientists to revise this model of the atom is that A small mass of positive charge known as proton, and a positive charge particle was discovered by Ernest Rutherford, in the center of the atom in the year 1900. Ernest Rutherford through his research resulted to splitting of the atom during nuclear reaction and proton was discovered.

Answer:

Al2(SO4)3

Explanation:

3Na2SO4 + 2AlCl3 →+ Al2(SO4)3 + 6NaCl

Answer:

16.8768 g

Explanation:

The reaction that takes place is:

First we convert the mass of hydrogen and oxygen into moles, using their respective molar masses:

There are significantly less oxygen moles than hydrogen moles, so oxygen is the limiting reactant.

We calculate the produced moles of water, using the moles of the limiting reactant:

Finally we convert water moles into grams, using its molar mass:

Answer:

b. Conceptual models help us see how things are related and how they connect or work together. This helps us develop a hypothesis based on changes in a variable and the corresponding response of another variable.

Explanation:

A conceptual model refers to a vivid representation or conceptualization of the working of a system. Hence conceptual models offer explanations to ideas about systems.

They help to fit all the facts together so that one can make sense of a system. Also, it helps us to understand how changes in one variable affects the other in a system, thereby helping us to formulate a testable hypothesis.

6.96 × 10²³ molecules NaNO₃

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Atomic Structure

Step 1: Define

98.2 g NaNO₃

Step 2: Identify Conversions

Avogadro's Number

Molar Mass of Na - 22.99 g/mol

Molar Mass of N - 14.01 g/mol

Molar Mass of O - 16.00 g/mol

Molar Mass of NaNO₃ - 22.99 + 14.01 + 3(16.00) = 85.00 g/mol

Step 3: Convert

Step 4: Check

Follow sig fig rules and round. We are given 3 sig figs.

6.95718 × 10²³ molecules NaNO₃ ≈ 6.96 × 10²³ molecules NaNO₃

Answer:

22g of  2

C

O

2

have  3.011×1023

3.011

×

10

23

  2

C

O

2

molecules.

Explanation:

Hope this helps! ^^

Answer:

A ) additional test/trial are needed

Answer:

B

Explanation:

The [OH⁻] of the solution : 1 x 10⁻¹¹ M

Given

[H30) : 1 x 10-3 M.

Required

the [OH]

Solution

The water equilibrium constant is a product of the concentrations of [H3O +] and [OH-]

Kw = [H₃O⁺] [OH⁻]

Input the value of  [H₃O⁺]

1 x 10⁻¹⁴ = 1 x 10⁻³ x  [OH⁻]

[OH⁻] = 1 x 10⁻¹⁴ :  1 x 10⁻³

[OH⁻] = 1 x 10⁻¹¹ M