first response gets brainliest

Answer:

I'd say maybe Dangerous? I hope this helps

Answer:

golden is sometimes referred to as shiny and beatitful

Explanation:

Answer:

Bohr placed the electrons in distinct energy levels.  Rutherford described the atom as consisting of a tiny positive mass surrounded by a cloud of negative electrons. Bohr thought that electrons orbited the nucleus in quantized orbits. Also, rutherfords was just a hypothesis while Bhor took the time to make his an experiment

Answer:

See explanation

Explanation:

Chemical reactions are also referred to as chemical change. A chemical change often leads to the formation of new substances and is not easily reversible.

A chemical reaction may be accompanied by the emission of heat and light, formation of a precipitate, evolution of gas, or a color change.

These observable physical effects may tell us weather a chemical reaction has taken place or not so we have to observe the system closely for any of these effects stated above.

Answer:

light

Explanation:

light is plasma, which is a state of matter

Answer:

What volume of water is produced when the CO2 reacts with the excess LiOH

X = 360 mL H2O

Explanation:

CO2 (g)       + 2 LiOH(s) ⇒ Li2CO3  (aq) + H2O(l)

20.0 mol        excess                                   x g

X = 360 mL H2O

x mL H20 = 20.0 mol CO2  (1 mol H2O /1 mol CO2)(18 g H2O/1 mol H2O)

(1 mL H2O /1 g H2O)

X = 360 mL H2O

Answer:

an attraction between a partially positive region in one molecule and a partially negative region in another molecule....dipole-dipole interaction

an attraction between two temporarily polarized molecules...dispersion forces

an attraction between a negatively charged particle and a partially positive region in a molecule....ion dipole interaction

an attraction between a partially positive hydrogen atom in a molecule and a partially negative and highly electronegative atom on another molecule....Hydrogen bonding

Explanation:

Some molecules have permanent dipole. As a result of this, the positive part of one molecule may attract the negative part of the other molecule leading to dipole-dipole interaction.

Dispersion forces occur in all molecules and is as a result of temporary polarization of a molecule due to instantaneous dipole–induced dipole attractions.

If a charged particle is attracted by a dipole in a molecule, we call it ion-dipole interaction.

When hydrogen is bonded to a highly electronegative element, the positive end of the dipole is on hydrogen while the negative end of the dipole is on the electronegative element. Molecular associations often result from this permanent dipole and is called hydrogen bonding, e.g, HF.

Answer:

5.27 g of NaCl

Explanation:

The balanced equation for the reaction is given below:

Na₂CO₃ + CaCl₂ —> 2NaCl + CaCO₃

Next, we shall determine the mass of CaCl₂ that reacted and the mass of NaCl produced from the balanced equation. This can be obtained as follow:

Molar mass of CaCl₂ = 40 + (35.5×2)

= 40 + 71

= 111 g/mol

Mass of CaCl₂ from the balanced equation = 1 × 111 = 111 g

Molar mass of NaCl = 23 + 35.5

= 58.5 g/mol

Mass of NaCl from the balanced equation = 2 × 58.5 = 117 g

Summary:

From the balanced equation above,

111 g of CaCl₂ reacted to produce 117 g of NaCl.

Finally, we shall determine the theoretical yield of NaCl. This can be obtained as follow:

From the balanced equation above,

111 g of CaCl₂ reacted to produce 117 g of NaCl.

Therefore, 5 g of CaCl₂ will react to produce = (5 × 117)/111 = 5.27 g of NaCl.

Thus, the theoretical yield of NaCl is 5.27 g.

Answer:

The Law of Conservation of Mass states that mass is neither created nor destroyed in chemical reactions. Since the number and type of atoms in the reactant side of the chemical equation are the same as on the product side, the Law of Conservation of Mass has been demonstrated.

Explanation:

In the answer.

The two main postulates that was given by Antoine Lavoisier are, oxygen play an important role in combustion and the other is mass of the reactant and product is conserved. Therefore, the given image is a good model for the Law of Conservation of Mass.

According to Law of conservation of mass, mass can neither be created nor be destroyed. Mass can only be transformed from one form to another. The law of conservation of mass was given by Antoine Lavoisier.

Every reaction in nature follow the law given by Antoine Lavoisier that is mass is always conserved. Another postulated that was given by Antoine Lavoisier is the role of oxygen in combustion reaction. Combustion can not happen without presence of oxygen.

The  image is a good model for the Law of Conservation of Mass as number and type of atoms on the reactant side and  product side are the same.

Therefore, the given image is a good model for the Law of Conservation of Mass.

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Answer: Energy of reactants = 30, Energy of products = 10

Exothermic

Activation energy for forward reaction is 10.

Explanation:

Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and [tex]\Delta H[/tex] for the reaction comes out to be negative.

Energy of reactants = 30

Energy of products = 10

Thus as energy of the product < energy of the reactant, the reaction is exothermic.

Activation energy [tex](E_a)[/tex] is the extra energy that must be supplied to reactants in order to cross the energy barrier and thus convert to products.

[tex]E_a[/tex] for forward reaction is (40-30) = 10.

Answer:

Answer:

Reversible

Explanation:

Changes of state are physical changes in matter. Common changes of the state include melting, freezing, sublimation, deposition, condensation, and vaporization.

Answer:

Molecules along the surface of a liquid behave differently than those in the bulk liquid.

Cohesive forces attract the molecules of the liquid to one another.

Water forming a droplet as it falls from a faucet is a primary example of surface tension.

Explanation:

Surface tension is the force that stretches the liquid surface. This force acts normal to the surface. It is the downward force that acts on the surface of the liquids which is due to the cohesive forces of the liquids.

The water molecules are bonded by a strong hydrogen bond force which is between hydrogen atom and the electronegative oxygen atom. At the surface the water molecules are attracted strongly by other water molecules which lies below the surface and are stretched at the surface. Thus the water molecules at the surface acts differently than in the bulk liquid.

Mercury have a strong cohesive force than the water and have a higher surface tension force than the water.

Surface water acquires minimum surface area, hence acquiring spherical shape of water.

Answer:

Explanation:

The average kinetic energy for an ideal gas is directly proportional to the temperature. The average kinetic energy of the gas is a measure of the temperature of the gas molecule

Also, the average speed is usually proportional to the square root of temperature.

Similarly, there is a noticeable increase in K.E and speed in regard to temperature but sometimes it is not usually proportional.

However, provided that there is more temperature in Xe as compared to He, then after the mixture of both takes place at equilibrium; the temperature tends to fluctuate between (25 - 50)°C

Thus, since there is a decrease in temperature in Xe, both the average kinetic energy as well as the speed too will also decrease.

The question is incomplete, the complete question is;

A student prepared several aqueous sodium chloride (NaCl) solutions to observe boiling point elevation at various molal concentrations, however, several errors were made throughout the procedure. Determine whether these errors would cause the observed boiling point to be increased or decreased relative to the expected boiling point, based on the procedure, or have no effect on the experimental results.

* The flask is washed with water but not thoroughly dried before preparing the solution

* The mass of NaCl used to prepare the solution is 5.400 grams instead of 4.400 grams

* Some of the prepared solution splashes out of the flask prior to observation of the boiling point

* When making the salt solution, 55.0 milliliters of water is added instead of 50.0 milliliters

Answer:

The flask is washed with water but not thoroughly dried before preparing the solution  - decrease

The mass of NaCl used to prepare the solution is 5.400 grams instead of 4.400 grams

-increase

Some of the prepared solution splashes out of the flask prior to observation of the boiling point- have no effect

When making the salt solution, 55.0 milliliters of water is added instead of 50.0 milliliters- decrease

Explanation:

If the flask is washed but not dried, then the solution will be further diluted than expected. As a result of this further dilution, the observed boiling point will be less than the expected boiling point because the boiling point depends on the solution's concentration.

If more solute is added than expected, the concentration of the solution is increased and the boiling point also increases above the expected boiling point due to the increase in amount of solute present.

If some of the solution splashes out of the flask prior to boiling, the boiling point is not affected because the concentration of the solution was not altered. The boiling point only changes when the concentration of the solution is changed.

If 55 ml of water is added instead of 50 ml, the solution is now more dilute than expected thereby reducing the concentration of the solution and the boiling point. Remember that, as the concentration of the solution decreases, the boiling point decreases accordingly.

Answer:

it went under the process known as crystalization

Explanation:

am a chemist

Answer:

C)Grassland biomes contain mostly grasses.

Explanation:

The main differences between a savanna biome and a grassland is that grasslands biomes contain mostly grasses.

Savanna are made up of both grasses and shrubs.

Answer:

Explanation:

here's the answer hope it helps! :)

Answer:

Silver Lake Picnic Area, Or C

Explanation:

Answer:

0.41 atm

Explanation:

A reaction between liquid reactants takes place at 10.0 °C in a sealed, evacuated vessel with a measured volume of 5.0 L. Measurements show that the reaction produced 13. g of sulfur hexafluoride gas. Calculate the pressure of sulfur hexafluoride gas in the reaction vessel after the reaction. You may ignore the volume of the liquid reactants. Round your answer to 2 significant digits.

Step 1: Given data

Step 2: Convert "T" to Kelvin

We will use the following expression.

K = °C + 273.15

K = 10.0 °C + 273.15 = 283.2 K

Step 3: Calculate the moles (n) of SF₆

The molar mass of SF₆ is 146.06 g/mol.

13. g × 1 mol/146.06 g = 0.089 mol

Step 4: Calculate the pressure (P) of SF₆

We will use the ideal gas equation.

P × V = n × R × T

P = n × R × T/V

P = 0.089 mol × (0.0821 atm.L/mol.K) × 283.2 K/5.0 L = 0.41 atm

Answer:

iconic bond is the answer

I hope it helps you ✌

Answer:

(a) 1s; has one orbital

(b) 4d; has five orbitals

(c) 3p; has three orbitals

(d) n=3 has nine orbitals

Explanation:

Electrons in an atom are always in constant motion, making it hard to predict there exact position. However, the most probable locations electrons can be be found are described with the terms shells, subshells and orbitals. A shell contains subshells and orbitals are found within subshells. The shells are given names such as K, L, M, N, which correspond to the principal quantum numbers, n = 1, 2, 3, and 4 respectively. There are 4 major types of subshells that can be found in a shell. They are named as s, p, d, f. Each subshell is composed of several orbitals.

a. 1s; the s subshell has only one orbital. Therefore, the 1s subshell has one orbital

b. 4d; the d subshell has five orbitals. Therefore, the 4d subshell has five orbitals

c. 3p; the p subshell has three orbitals. Therefore, the 3d subshell has  three orbitals

d. n = 3; the shell with n = 3 has the following subshells, 3s, 3p, 3d.the number of orbitals will be 1 + 3 + 5 = 9 orbitals. Therefore, the number of orbitals in n = 3 is nine orbitals

Answer:

See explanation below

Explanation:

There are several ways to know if an acid or base is strong. One method is calculating the pH. If the pH is really low, is a strong acid, and if it's really high is a strong base.

However we do not have a pH value here.

The other method is using bronsted - lowry theory. If an acid is strong, then his conjugate base is weak. Same thing with the bases.

Now, Looking at the 4 compounds, we can say that only two of them is weak and the other two are strong compounds. Let's see:

LiOH ---> Strong. If you try to dissociate :

LiOH ------> Li⁺ + OH⁻     The Li⁺ is a weak conjugate acid.

HF -----> Weak

HF --------> H⁺ + F⁻   The Fluorine is a relatively strong conjugate base.

HCl -----> Strong

This is actually one of the strongest acid.

NH₃ ------> Weak

Now writting the Ka and Kb expressions:

Ka = [H⁺] [F⁻] / [HF]

Kb = [NH₄⁺] [OH⁻] / [NH₃]

Finally, to calculate the [OH⁻] we need to use the following expression:

Kw = [H⁻] [OH⁻]

Solving for [OH⁻] we have:

[OH⁻] = Kw / [H⁺]

Remember that the value of Kw is 1x10⁻¹⁴. So replacing:

[OH⁻] = 1x10⁻¹⁴ / 7x10⁻⁶

[OH⁻] = 1.43x10⁻⁹ M

And now, multiplying by 10¹⁰ we have:

[OH⁻] = 1.429x10⁻⁹ * 1x10¹⁰

Hope this helps

Strong acids and bases are those which completely ionized in body fluid, and weak acids and bases are those who does not completely ionized in body fluid.

Ka expression is used to differentiate between strong and weak acids.

[tex]\bold{\dfrac{[H+][F-]}{[HF]}}[/tex]

[tex]\bold{\dfrac{[NH_4^+] [OH^-]}{[NH_3]} }[/tex]

Given, [tex]\bold{ [H^+]=1\times10^-^6\; at \;25^oC}[/tex]

We know, [tex]\bold{ [H^+]\times[OH^-]=1\times10^-^6\; at \;25^oC}[/tex]

[tex]\bold{[OH^-]=\dfrac{1\times10^-^1^4}{6.2\times10^-^6} = 1.43\times10^-^9}[/tex]

Now, multiplying the value by [tex]10^1^0[/tex]

[tex]\bold{( 1.429\times10^-^9) \times 1\times10^1^0= 14.29}[/tex]

Thus, the value is 14.29.

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Answer:

Explanation:

a )

H₂O₂ (aq) + 2 Fe²⁺ (aq) + 2 H⁺  = 2H20 (l) + 2 Fe³⁺(aq)

Here oxidation number  of Fe is increasing from + 2 to + 3 so it is being oxidized . Hence H₂O₂ is acting as oxidizing agent here .

b )

5 H₂O₂ (aq) + 2 MnO₄⁻¹ (aq) + 6 H⁺ (aq) → 8 H20 (l) + 2 Mn⁺² (aq) + 5O₂ (g)

In this reaction,  oxidation number of Mn is reducing from + 7 to + 2 so it is being reduced . Here H₂O₂ is acting as reducing agent .

Answer:

1.93 x 10²⁶ formula units

Explanation:

Given parameters:

Number of moles of LiCl  = 3.2 x 10² moles  = 320moles

Unknown:

Number of formula units in this compound  = ?

Solution:

The mole is used a reference to determine the number of substances matters contain.

 A mole contains the Avogadro's number of particles.

 So;

       1 mole of a substance contains 6.02 x 10²³ formula units;

320 moles of LiCl will contain 320 x  6.02 x 10²³  = 1.93 x 10²⁶ formula units

Answer:

58.61 grams

Explanation:

Taking The molecular weight of NaCl = 58.44 grams/mole

Determine how many grams of NaCl to prepare the bath solution

first we will calculate the moles of NaCl that is contained in 6L of 170 mM of NaCI solution

= ( 6 * 170 ) / 1000

= 1020 / 1000 = 1.020 moles

next

determine how many grams of NaCl

= moles of NaCl * molar mass of NaCl

= 1.020 * 58.44

= 58.61 grams

The molecular formula : C₁₈H₁₈N₈

Given

62.41% C, 5.24% H, and 32.36% N

Required

The molecular formula

Solution

mol ratio

C : 62.41/12.0096 = 5.1967

H : 5.24/1.00784 = 5.1992

N : 32.36/14.0067 = 2.310

Divide by 2.310(smallest)

C : 5.1967/2.31=2.25

H : 5.1992/2.31 = 2.25

N : 2.31/2.31 = 1

Multiplied by 4

C : H : N = 9 : 9 : 4

The empirical formula : C₉H₉N₄

(C₉H₉N₄)n=346.40 g/mol

(12.0096 x 9 + 1.00784 x 9 + 14.0067 x 4)n=346.4

(108.0864+9.07056+56.0268)n=346.4

(173.184)n=346.4

n=2

The molecular formula : C₁₈H₁₈N₈

Answer:

Partial pressures:

PCl₅ = 0.558 atm

PCl₃ = 0.22 atm

Cl₂ = 0.22 atm

Explanation:

From the given information:

The number of moles of PCl₅ associated with the evaporation is:

[tex]n_{PCl_5}= \dfrac {weight \ of \ PCl_5} {M.Wt. \ of \ PCl_5}[/tex]

[tex]n_{PCl_5}= \dfrac {2.69 \ g} {208.5 \ g/mol}[/tex]

[tex]n_{PCl_5}= 0.013 \ mol[/tex]

Temperature of the gas = 250° C = (250 + 273.15) K

= 523.15 K

Using the Ideal gas equation to determine the pressure exerted by the completely vaporized PCl₅

PV = nRT

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

[tex]P = \dfrac{0.0013 \ mol \times 0.082 \ Latm^0 K^{-1} . mol ^{-1} \times 523.15 \ K}{1.0 \ L}[/tex]

P = 0.558 atm

Thus, at  250° C, decomposition of PCl₅ occurs.

In the container, PCl₅  decomposes to PCl₃ and Cl₂.

i.e.

[tex]PCl_{5(g)} \to PCl_{3(g)}+ Cl_{2(g)}[/tex]

Using Dalton's Law:

[tex]P_{total } =P_1 + P_2+P_3 +...[/tex]

[tex]P_1 = P_{Total} \times X_1[/tex]

where;

X = mole fraction

Then, the total no. of moles in the container is:

[tex]n = \dfrac{PV} {RT}[/tex]

[tex]n = \dfrac{1\ atm \times 1.0\ L}{0.0821 \ L \ atm \ K^{-1}.mol \times 523.15\ K}[/tex]

n = 0.023 mol

Now, the container contains a total amount of 0.023 mol where initially 0.013 mol are that of PCl₅ and remaining 0.005 mol of PCl₃ and 0.005 mol of Cl₂.

Thus, the partial pressure of  PCl₃  is:

[tex]P__{PCL_3} }= P_{total} \times \dfrac{no. \ of \ moles \ of PCl_5}{total \ no. \ of \ moles}[/tex]

[tex]P__{PCL_3}} = 1 \ atm \times \dfrac{0.005}{0.023}[/tex]

[tex]P__{PCL_3}} = 0.22 \ atm[/tex]

Thus, since the no of moles of PCl₃ and Cl₂ are the same, then the partial pressure for Cl₂ is = 0.22 atm

The temperature and the strength of the metallic link are the two most crucial variables that can impact how malleable a metal or alloy is.

A metal is a substance that has a shiny look when freshly processed, polished, or shattered, and conducts electricity and heat rather effectively. Generally speaking, metals are malleable and ductile.

The amount of pressure that a metal can sustain without breaking can be used to gauge its malleability. Varied metals have different degrees of malleability because of variations in their crystal structures.

The temperature of the metal and the strength of the metallic connection are the two parameters that define how malleable a metal or metal alloy will be.

Thus,  The kind of the metallic connection can have a significant impact on how easily metal atoms can rearrange themselves.

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Answer:

1. 0.74mol

2. 0.42mol

3. 2.125mol

4. 0.301mol

5. 4.52 × 10^23 particles

Explanation:

Number of moles (n) in a substance can be found using the formula:

mole (n) = mass/molar mass

Using this formula, the following moles are calculated:

1. Molar of Na = 23g/mol

mole = 17/23

mole = 0.74mol

2. Molar mass of Na2SO4 = 23(2) + 32 + 16(4)

= 46 + 32 + 64

= 142g/mol

Mole = 60/142

mole = 0.42mol

3. Molar mass of CO2 = 12 + 16(2)

= 12 + 32

= 44g/mol

mole = 93.5/44

mole = 2.125mol

4. Molar mass of sodium nitrate (NaNO3) = 23 + 14 + 16(3)

= 23 + 14 + 48

= 85g/mol

mole = 25.6/85

mole = 0.301mol

5. Number of particles in one mole of a substance is 6.022 × 10^23 particles. Hence, in 0.75mol of calcium hydroxide (Ca(OH)2, there will be;

0.75mol × 6.02 × 10^23

= 4.515 × 10^23

= 4.52 × 10^23 particles

Answer:

4

Explanation:

the one you ARE ON

Answer: Equation 1, because Zn being more reactive, replaces Ag from AgNO3

Explanation: I got it right on the quiz and it replaces it