PLEASE HELP!
this is due tomorrow and i really need help!!! this is for my final grade! thank you

Answer:

Silicon

Explanation:

Nucleus

14 protons

Group 14

Number 14

+4, +2, or -4

Answer:

Explanation:

Name of the part of this atom labeled z is nucleus.

number of protons is 14 .

the given element is silicion and it lies in group 14.

the no of period that contains this element is  3.

charge formed on the ion formed from this atom is positive charge because it gives 4 electron to other element .

If the element gains the electron then it has negative charge where as when it loses it will have positive charge.

Answer:

D es pero que te ayude amigo

Answer: equivalent amounts of sodium hydroxide and a solution of sodium hydrogen carbonate

Explanation:

Answer:

La masa de Bi (NO₃) ₃ producida es de aproximadamente 2.117,09 gramos

Explanation:

La ecuación química de la reacción se presenta como sigue;

2Mn (NO₃) ₂ + 5NaBiO₃ + 14HNO₃ → 2HMnO₄ + 5Bi (NO₃) ₃ + 5NaNO₃ + 7H₂O

La masa dada de Mn (NO₃) ₂ = 650 g

La masa de NaBiO₃ = 750 g

El número de moles de Mn (NO₃) ₂ = 650 g / (178.95 g / mol) ≈ 3.63 moles

El número de moles de NaBiO₃ = 750 g / (279.968 g / mol) ≈ 2.68 moles

Por lo tanto, el NaBiO₃, es el reactivo limitante, y el rendimiento teórico de Bi (NO₃) ₃ ≈ 5/2 × 2.68 = 6.7 moles

Dado que la eficiencia del proceso es del 80%, el rendimiento real de Bi (NO₃) ₃ = 0,8 × 6,7 moles = 5,36 moles de Bi (NO₃) ₃

La masa molar de Bi (NO₃) ₃ ≈ 394,98 g / mol

La masa de Bi (NO₃) ₃ = 394,98 g / mol × 5,36 moles ≈ 2,117,09 g

La masa de Bi (NO₃) ₃ produjo ≈ 2,117.09 g

Answer:

B. 2.14 x 10^-19 J

Explanation:

The energy of a wave of light can be obtained using the equation:

E = h*c/λ

Where E is the energy in joules,

λ is wavelength = 930nm = 930x10⁻⁹m

h = Planck's constant = 6.626x10⁻³⁴Js

c = Speed of light = 3.00x10⁸m/s

Replacing:

E = 6.626x10⁻³⁴Js*3.00x10⁸m/s/930x10⁻⁹m

E = 2.14x10⁻¹⁹J

Right option is:

Answer:

The X ray’s wavelength is 4.61*10⁻¹¹ m

Explanation:

Wavelength is the minimum distance between two successive points on the wave that are in the same state of vibration. It is expressed in units of length (m).

Frequency is the number of vibrations that occur in a unit of time. Its unit is s⁻¹ or hertz (Hz).

The propagation speed is the speed with which the wave propagates in the medium, that is, it is the magnitude that measures the speed at which the wave's disturbance propagates along its displacement. Relate the wavelength (λ) and the frequency (f) inversely proportional using the following equation:

v = f * λ.

In this case:

Replacing:

3*10⁸ [tex]\frac{m}{s}[/tex]= 6.5*10¹⁸ Hz* λ

Solving:

[tex]wavelength= \frac{3*10^{8} \frac{m}{s} }{6.5*10^{18} Hz}[/tex]

λ= 4.61*10⁻¹¹ m

The X ray’s wavelength is 4.61*10⁻¹¹ m

Answer:

Na has atomic number 11

which is less than magnesium has atomic number 12

ANSWER IS D

Explanation:

aluminum or Al is atomic 13 and Ca or calcium is atomic number 20 and rubidium or Rb is atomic number 37

Explanation:

A B C D isme koyi ans hain doond lo

Answer: In the given reactions neither reaction 1 nor 2 reaction leads to an increase in entropy.

Explanation:

The degree of randomness present in the molecules of a substance is called entropy.

In gases, molecules are held by weak forces due to which they move apart from each other. Hence, they have high entropy.

In liquids, molecules are a little close to each other so they have less entropy than gases.

In solids, molecules are tightly held together so they have least or negligible entropy.

As reaction 1 is [tex]CaO(s) + CO_{2}(g) \rightarrow CaCO_{3}(s)[/tex] and it shows that product is in solid state. Therefore, entropy is decreasing.

As reaction 2 is [tex]H_{2}O(g) \rightarrow H_{2}O(l)[/tex] and it shows that gas is converted into liquid. Therefore, entropy is also decreasing here.

Thus, we can conclude that in the given reactions neither reaction 1 nor 2 reaction leads to an increase in entropy.

Answer: Neither Reaction 1 nor 2

Explanation:

Answer:

Proton & neutron

Explanation:

electrons only affect the charge. neutrons affect the mass and stability of an atom.

Oxidation reaction

Hope this helps! :)

Answer:

gallium

Explanation:

it is the old melting in a hot cup of coffee spoon

Answer:

Elements That Are Liquid at 25°C

•Bromine

•mercury

Explanation:

The metal which exist as a liquid at room temperature is mercury.

Non-metal which exist as a liquid at room temperature is bromine.

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Answer:

[tex]{ \boxed{ \tt{formular : pH = - log[H {}^{ + } ]}}} \\ pH = - log(1.00 \times {10}^{-6} ) = 6: it's an acid\\ since \: we \: lack \: the \: exponent, \: this \: question \: is \: unsolvable \\ { \green{ \bf{take \: note}}} :{ \tt{pH \: below \: 7 \: that \: is \: { \red{acidic}}. \: \: pH \: greater \: than \: 7 \: is \: { \red {basic}}}}[/tex]

Answer:

All substances can be characterized by their unique sets of physical and chemical properties. Properties that can be determined without changing the composition of a substance are referred to as physical properties. Characteristics such as melting point, boiling point, density, solubility, color, odor, etc.

Answer:

s1 to GS as the amount of energy required to remove the electron is greatest when it is closest to the nucleus.

Explanation:

Fun facts:

When the electron changes levels, it decreases energy and the atom emits photons. The photon is emitted with the electron moving from a higher energy level to a lower energy level. The energy of the photon is the exact energy that is lost by the electron moving to its lower energy level.

Answer:

The answer is: S.1 to G.S

Hope this helpss :) <3

Explanation:

Answer:

[tex]CH _{3}CH(CH _{3})CH _{2}COO {}^{ - } \\ \\ [/tex]

Answer: The volume of the solution is 28.75 mL

Explanation:

Molarity is defined as the amount of solute expressed in the number of moles present per liter of solution. The units of molarity are mol/L. The formula used to calculate molarity:

[tex]\text{Molarity of solution}=\frac{\text{Given mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution (mL)}}[/tex] .....(1)

Given values:

Molarity of copper nitrate = 0.560 M

Given mass of copper nitrate = 3.02 g

Molar mass of copper nitrate = 187.56 g/mol

Putting values in equation 1, we get:

[tex]0.560=\frac{3.02\times 1000}{187.56\times \text{Volume of solution}}\\\\\text{Volume of solution}=\frac{3.02\times 1000}{187.56\times 0.560}=28.75mL[/tex]

Hence, the volume of the solution is 28.75 mL

Answer:

false

Explanation:

standard form is Potassium hydrogen phthalate

Answer:

High pH negatively affected the germination rate of seeds from most species, but had no effect on the per cent germination of any of the species. The higher concentration of the nutritious solutions affected negatively the germination level and rate

Explanation:

Answer:

boiling point, temperature at which the pressure exerted by the surroundings upon a liquid is equaled by the pressure exerted by the vapour of the liquid; under this condition, addition of heat results in the transformation of the liquid into its vapour without raising the temperature.

Explanation:

Radhe Radhe❤

Explanation:

The point at which a matter melts is called boiling or melting point.

Answer: Boiling point of the given solution is [tex]102.048^{o}C[/tex].

Explanation:

Given: Molality = 2.00 m

[tex]k_{b} = 0.512^{o}C[/tex]

Now, equation for dissociation of water is as follows.

[tex]H_{2}O \rightarrow H^{+} + OH^{-}[/tex]

As it is giving 2 ions upon dissociation. So, the value of i = 2.

Formula used to calculate change in temperature is as follows.

[tex]\Delta T = i \times k_{b} \times m[/tex]

where,

i = Van't Hoff factor

[tex]k_{b}[/tex] = molal boiling point elevation constant

m = molality

Substitute the values into above formula as follows.

[tex]\Delta T = i \times k_{b} \times m\\= 2 \times 0.512^{o}C \times 2.00 m\\= 2.048^{o}C[/tex]

As the boiling point of water is [tex]100^{o}C[/tex]. Hence, the boiling point of solution will be as follows.

[tex]\Delta T^{'}_{b} = 100^{o}C + 2.048^{o}C\\= 102.048^{o}C[/tex]

Thus, we can conclude that boiling point of the given solution is [tex]102.048^{o}C[/tex].

Answer:

concentration = mol/volume = 4/2 = 2M

Answer:

[tex]a = \frac{24.79078- 1.7161b}{1.310 - b}[/tex]

[tex]b = 1.310 - \frac{22.5427}{a - 1.7161}[/tex]

Explanation:

Given

[tex]P = 1\ atm[/tex]

[tex]V = 1.310\ L[/tex]

[tex]T =160\ K[/tex]

Required

Solve for a and b

Van Der Waals equation is:

[tex]P = \frac{RT}{V - b} - \frac{a}{V^2}[/tex]

Substitute values for P, V and T, we have:

[tex]1 = \frac{R*160}{1.310 - b} - \frac{a}{1.310^2}[/tex]

R is a constant and the value is:

[tex]R = 0.0821[/tex]

So, the equation becomes:

[tex]1 = \frac{0.0821*160}{1.310 - b} - \frac{a}{1.310^2}[/tex]

Simplify the expression

[tex]1 = \frac{13.136}{1.310 - b} - \frac{a}{1.7161}[/tex] ----- (a)

Solving for (a):

[tex]1 + \frac{13.136}{1.310 - b} = \frac{a}{1.7161}[/tex]

Multiply both sides by 1.7161

[tex]a = [1 + \frac{13.136}{1.310 - b}] * 1.7161[/tex]

Take LCM

[tex]a = [\frac{1.310 - b+13.136}{1.310 - b}] * 1.7161[/tex]

Evaluate like terms

[tex]a = [\frac{14.446- b}{1.310 - b}] * 1.7161[/tex]

Open bracket

[tex]a = [\frac{24.79078- 1.7161b}{1.310 - b}[/tex]

Solving for (b), we have:

[tex]1 + \frac{13.136}{1.310 - b} = \frac{a}{1.7161}[/tex]

Subtract 1 from both sides

[tex]\frac{13.136}{1.310 - b} = \frac{a}{1.7161}-1[/tex]

Take LCM

[tex]\frac{13.136}{1.310 - b} = \frac{a-1.7161}{1.7161}[/tex]

Inverse both sides

[tex]\frac{1.310 - b}{13.136} = \frac{1.7161}{a - 1.7161}[/tex]

Multiply both sides by 13.136

[tex]1.310 - b = 13.136 * \frac{1.7161}{a - 1.7161}[/tex]

[tex]1.310 - b = \frac{22.5427}{a - 1.7161}[/tex]

Collect like terms

[tex]b = 1.310 - \frac{22.5427}{a - 1.7161}[/tex]

Answer:

EF-2

hurricane/tropical cyclone

recurrent weather

The two types of downbursts are macrobursts and microbursts. A macroburst affects an area that's greater than 2.5 miles across. A microburst affects an area that's less than 2.5 miles across.

A funnel cloud forms as a spinning column of air that descends from a thundercloud. However, a funnel cloud doesn't become a tornado until it actually touches the ground. Once it touches the ground, where it begins to pick up dust and debris, it becomes a tornado.

Tropical cyclones, such as hurricanes, are fueled by warm ocean waters. Once they make landfall, they lose this fuel source and begin to lose strength.

The heat index and the wind chill index are similar because both consider other factors that affect how air temperature feels. The heat index considers relative humidity in relation to air temperature. Higher humidity makes air temperatures feel hotter. The wind chill index considers wind speed in relation to air temperature. Higher wind speeds make air temperatures feel colder.

Heat waves—Heat waves can be very dangerous when accompanied by high humidity. The human body depends on evaporation of sweat to cool itself down on hot days. When humidity levels are high, the rate of evaporation slows down. Consequently, it becomes harder for the body to cool itself and much easier for the body to overheat.

Explanation:

took the testoronee

Answer:

Among the given reactions,

a. Ag+FeCl 3

b, Zn + CaO

C. Ba+Na 2 CO 3

d . Cr+KNO3

which reaction is likely to take place based on the reactivity series?

Explanation:

The metal reactivity series is:

Li > K> Ba >Ca>Na > Mn > Zn > Cr> Fe> Cd Ni > H > Sb > Cu > Ag > Pd > Hg > Pt

The highly reactive metal will displace the less reactive metal from its compound during a displacement reaction.

a. Ag+FeCl 3

Ag is less reactive than Fe, so Ag cannot displace Fe from its compound.

This reaction also does not occur.

b, Zn + CaO

Zn is less reactive than Ca, so it cannot displace Ca from its compound.

This reaction does not occur.

C. Ba+Na 2 CO 3

Ba is more reactive than Na, so Ba displaces Na from its compound.

This reaction is possible.

d . Cr+KNO3

Cr is less reactive than K, so it cannot displace K from its compound.

Hence, This reaction is not possible.

Answer:

option c) Ba+Na 2 CO 3 -> BaCO3 +2Na

Answer:

Answer:

The Ideal gas law

Explanation:

From the given question, we have:

V [tex]\alpha[/tex] [tex]\frac{nT}{P}[/tex]

where each variable has its usual meaning.

Thus,

V = [tex]\frac{nRT}{P}[/tex]

where R is the ideal gas constant

cross multiply to have;

PV = nRT

This implies that the volume of the gas is directly proportional to the number of moles of the gas.

Therefore, the law can be used to determine the relationship between the volume and number of moles is the ideal gas law.