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Answer:

The mechanical energy of the system increases, provided there is no loss of energy due to friction. The energy would transform to kinetic energy when the speed is increasing. The mechanical energy of the system remains constant provided there is no loss of energy due to friction.

Explanation:

Answer:

Where is the phase melting graph? Can't seem to find it

Explanation:

1 metal they are likely to lose an electron

2non metals

3 Nobel gases because they are not reactive with stable valance number

Answer:

MARK AS BRAINLIST

Explanation:

density = mass/volume

mass=25.3

density =10.5

10.5=25.3/v

v=25.3/10.5

=2.40

Answer:

it is 75 degrees

Explanation:

Volume is 138.7 mL.

The equation for calculation of volume is as follows:-

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

STP:-

Temperature=273 K

Pressure=1 atm

[tex]\frac{1 atm\times250mL}{273 K} =\frac{2 atm\times V_2}{303\ K}\\V_2=138.7\ mL[/tex]

Hence, the volume is 138.7 mL.

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The daughter isotope (a decay product): Polonium (Po)

Radioactivity is the process of unstable isotopes to stable isotopes by decay, by emitting certain particles,  

Radon-222 emits alpha α particles ₂He⁴  , so the atomic number decreases by 2, mass number decreases by 4

Reaction

[tex]\tt _{86}^{222}Rn\Rightarrow _{84}^{218}+_2^4He[/tex]

1. The mass number of the daughter isotope = 218

2 and 3. If we look at the periodic system, the element with atomic number 84 is Polonium (Po)

3Zn + 8HNO₃⇒ 3Zn(NO₃)₂ + 2NO + 4H₂O

Equalization of chemical reaction equations can be done using variables. Steps in equalizing the reaction equation:  

For gas combustion reaction which is a reaction of hydrocarbons with oxygen produces CO₂ and H₂O (water vapor). can use steps:  

Balancing C atoms, H and the last O atoms

Reaction

Zn + HNO₃⇒ Zn(NO₃)₂ + NO + H₂O

aZn + bHNO₃⇒ Zn(NO₃)₂ + cNO + dH₂O

Zn : left = a, right =1 ⇒a=1

H : left = b, right = 2d⇒ b=2d (eq 1)

N : left = b, right = 2+c⇒b=2+c (eq 2)

O : left = 3b, right = 6+c+d ⇒3b=6+c+d(eq 3)

3(2d)=6+c+d

6d=6+c+d

5d=6+c (eq 4)

3(2+c)=6+c+d

6+3c=6+c+d

2c=d (eq 5)

5(2c)=6+c

10c=6+c

9c=6

c = 2/3

d = 2 x 2/3

d = 4/3

b = 2 x 4/3

b = 8/3

The equation

aZn + bHNO₃⇒ Zn(NO₃)₂ + cNO + dH₂O to

Zn + 8/3HNO₃⇒ Zn(NO₃)₂ + 2/3NO + 4/3H₂O x 3

3Zn + 8HNO₃⇒ 3Zn(NO₃)₂ + 2NO + 4H₂O

Answer:

C: amount of mass in a certain volume

Explanation:

Just took the quiz and got 100%

Answer:

Explanation:

The mass of a substance when given the density and volume can be found by using the formula

From the question

density = 2 g/ml

volume = final volume of water - initial volume of water

volume = 508 - 500 = 8 mL

We have

mass = 2 × 8

We have the final answer as

Hope this helps you

Answer:

B. How many of each atom are present in the compound

D. the simplified ratio of atoms in relation to each other

Explanation:

In a chemical formula, chemical elements or atoms are represented by a chemical symbol for example Fe for iron and Na for sodium, and the number of each atom is represented by a subscript such as CO2, where 2 is a subscript representing 2 atoms of oxygen.

A subscript represents the number of each atom in the compound and the simplified ratio of atoms in relation to each other. The simplified ratio of atoms in relation to each other means subscript shows the contribution of both the atoms in the compound, for example: N2 + 3H2 => 2NH3, it means the subscript showing the ratio or proportionate of atoms that is 2:2 for both nitrogen and hydrogen.

The subscript is always written below and to the right of the chemical symbol.

Hence, the correct answer is "B. How many of each atom are present in the compound and D. the simplified ratio of atoms in relation to each other"

Answer:

Drawing Conclusions

Explanation:

You put together your observations and can finally decide if your hypothesis was right or not.

Answer:

water vapour is there

Explanation:

thats all i know

Answer:

Explanation:

The density of a substance can be found by using the formula

[tex]density = \frac{mass}{volume} \\ [/tex]

From the question

mass = 102 g

volume = 24.5 mL

We have

[tex]density = \frac{102}{24.5} \\ = 4.163265306...[/tex]

We have the final answer as

Hope this helps you

Answer:

i think it is letter b. rustability but not so sureeee

Answer:

carbon dioxide CO[tex]{2}[/tex]

Explanation:

Double Polar Covalent bonds with CO2

Explanation:

Keep in mind that CO2 is a nonpolar molecule

Answer:

La fórmula empírica y molecular es: C₂H₆O.

Explanation:

Para calcular la formula empírica y molecular del compuesto debemos primero plantear la reacción:  

[tex] C_{x}H_{y}O_{z} + O_{2} \rightarrow CO_{2} + H_{2}O [/tex]

Necesitamos encontrar "x", "y" y "z". Para ello, tenemos que recordar que la masa de carbono e hidrógeno producida está relacionada con la cantidad de C y H inicial (del compuesto):

Para el H:

CHO → H₂O

y          5,4g

[tex] \frac{2*1 g}{18 g} = \frac{y}{5,4 g} \rightarrow y = 0,6 g [/tex]

Para C:  

CHO → CO₂

 x         8,8g

[tex] \frac{12 g}{44 g} = \frac{x}{8,8 g} \rightarrow x = 2,4 g [/tex]

Para el O:

[tex] z = 4,6 g - 2,4 g - 0,6 g = 1,6 g [/tex]

Ahora mediante el calculo de los moles del C, H y O podemos encontrar la fórmula empírica:

Para el H:

[tex] n_{y} = \frac{m}{Pm} = \frac{0,6 g}{1 g/mol} = 0,6 moles [/tex]

Para el C:

[tex] n_{x} = \frac{m}{Pm} = \frac{2,4 g}{12 g/mol} = 0,2 moles [/tex]

Para el O:

[tex] n_{z} = \frac{m}{Pm} = \frac{1,6 g}{16 g/mol} = 0,1 moles [/tex]

[tex] C_{\frac{n_{x}}{n_{z}}}H_{\frac{n_{y}}{n_{z}}}O_{\frac{n_{z}}{n_{z}}} = C_{\frac{0,2}{0,1}}H_{\frac{0,6}{0,1}}O_{\frac{0,1}{0,1}} = C_{2}H_{6}O_{1} [/tex]

Entonces, la fórmula empírica del commpuesto formado es C₂H₆O.

Ahora para determinar la fórmula molecular podemos usar la siguiente relación:

[tex] \frac{Pm}{Pm_{e}} = n [/tex]

[tex] F_{m} = n*F_{e} [/tex]

[tex] F_{m} = \frac{Pm}{Pm_{e}}*F_{e} [/tex]    

En donde Fm (fórmula molecular) y Fe (fórmula empírica) están relacionadas por n.

El valor de Pm lo obtenemos de la ecuación del gas ideal:

[tex]PV = nRT = \frac{m}{Pm}RT[/tex]

[tex] Pm = \frac{mRT}{PV} = \frac{9,2 g*0,082 L*atm/(K*mol)*(90 + 273 K)}{1.02 atm*5,80 L} = 46,3 g/mol [/tex]

[tex] F_{m} = \frac{46,3 g/mol}{(2*12 + 6*1 + 16)g/mol}*C_{2}H_{6}O_{1} = 1.00*C_{2}H_{6}O_{1} = C_{2}H_{6}O_{1} [/tex]    

Por lo tanto, la fórmula molecular es la misma que la fórmula empírica, a saber C₂H₆O.

Espero que te sea de utilidad!

Answer:

Steps of a scientific investigation include 1. make observation

2. ask a question

3. form a hypothesis

4. test the hypothesis

5. analyze results

5 , drawing conclusions,

6. and communicating the results

Answer:

Period 4, group 5- Vanadium

Period 5, group 7- Technetium

Period 7, group 5- Dubnium

Period 5, group 4- Zirconium

Explanation:

Answer:

B - BF3

Explanation:

BF3 has 3 bonds around the central atom and now lone pairs on it. This matches the geometry of a trigonal planar molecule as per the VSEPR Model.

Molecules have two distinct characteristics: form and geometry. Geometry includes the lone pair encircling the focal element whereas shape excludes it. Therefore, the correct option is option B.

Valence shell electron repulsive force is what VSEPR stands for. Based on the valence electron pairs that are prevalent around the core element of the molecule, the VSEPR theory is employed to predict the structure and geometry of molecules.

According to VSEPR theory, Lone pair lone pair repulsion is greater than bond pair bond pair repulsion. The core atom of BF[tex]_3[/tex] is surrounded by three bonds and contains no lone pairs. According to the VSEPR Model, this corresponds to the geometry of such a trigonal planar molecule.

Therefore, the correct option is option B.

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Answer:

1875 nm

Explanation:

Given the Rydberg formula for hydrogen: 1/λ = R(1/n₁² - 1/n₂²)

where R ≈ 1.097* 10^7 /m

Hence;

1/λ = 1.097* 107/m * (1/3² - 1/4²) = 5.3 * 10^5/m

λ = 1.875 * 10-6 m = 1875 nm

Answer:

Rocks

Explanation:

The combined aggregation of minerals​  are called rocks. There are three types of rocks Igneous Rocks, sedimentary rock, and metamorphic rocks.

Rocks are formed due to the repetitive, orderly, geometrical internal arrangement of minerals. Minerals undergo several processes such as weathering, crystallization, erosion, and sedimentation to form rocks.

Hence, the combined aggregation of minerals​  is called rocks.

Answer:

3.  The total number of protons and neutrons in an atom is its mass number.

4.  The mass number of a helium atom with 2 protons and 2 neutrons is 4.

5.  A beryllium atom with 4 protons and a mass number of 9 has 5 neutrons.

6.  The chemical symbol is Ne.   The atomic number is 10.  The mass number is 22.

7.  Neon-22

8.  Not enough information

Answer:

Explanation: The correct answer is 1. Do not put 2 .

Answer:

[tex]\boxed {\tt Kinetic \ energy}[/tex]

Explanation:

First, let's define kinetic energy and potential energy.

Kinetic

Potential

Since the boy is walking down the street, the boy is in motion. Therefore, the energy must be kinetic energy.

Answer:

So I don't know what do you mean by that, please be a little specific.

Explanation:

^^