The Big Bang really happened. But within milliseconds, the universe expanded or inflated so rapidly that the universe is flat and uniform

Answer :

                      (D) [tex](NH_{4})_{2}S[/tex]      (C) [tex]Ba(NO_{3})_{2}[/tex]            (B) [tex]CuCl_{2}[/tex]

(A) [tex]K_{2}SO_{4}[/tex]                _                     [tex]BaSO_{4}[/tex]                          _

(B) [tex]CuCl_{2}[/tex]             [tex]Cu_{2}S_{2}[/tex]                     _                          

(C) [tex]Ba(NO_{3})_{2}[/tex]            BaS  

Explanation :

(1) Reaction for A + B

[tex]K_{2}SO_{4}[/tex] + [tex]CuCl_{2}\rightarrow[/tex] 2KCl + [tex]CuSO_{4}[/tex]

In this reaction, there is no precipitate formed as the products are souble.

(2) Reaction for A + C

[tex]K_{2}SO_{4}[/tex] + [tex]Ba(NO_{3})_{2}\rightarrow[/tex] [tex]BaSO_{4}[/tex] + [tex]KNO_{3}[/tex]

In this reaction, [tex]BaSO_{4}[/tex] is formed as precipitate as it do not dissolve.

(3) Reaction for A + D

[tex]K_{2}SO_{4}[/tex] + [tex](NH_{4})_{2}S\rightarrow[/tex] [tex]K_{2}S[/tex] + [tex](NH_{4})_{2}SO_{4}[/tex]

In this reaction, there is no precipitate formed as the products are souble.

(4) Reaction for B + D

[tex]2CuCl_{2}[/tex] + [tex]2(NH_{4})_{2}S\rightarrow[/tex] [tex]4NH_{4}Cl+Cu_{2}S_{2}[/tex]

In this reaction, [tex]Cu_{2}S_{2}[/tex] is formed as precipitate as it do not dissolve.

(5) Reaction for B + C

[tex]CuCl_{2}[/tex] + [tex]Ba(NO_{3})_{2}\rightarrow[/tex] [tex]BaCl_{2}[/tex] + [tex]Cu(NO_{3})_{2}[/tex]

In this reaction, there is no precipitate formed as the products are souble.

(6) Reaction for C + D

[tex]Ba(NO_{3})_{2}[/tex] + [tex](NH_{4})_{2}S\rightarrow[/tex] BaS + [tex]2NH_{4}NO_{3}[/tex]

In this reaction, BaS is formed as precipitate as it do not dissolve.

The initial temperature of the water was 56.7 °C.

Step 1. Calculate the temperature change.

The formula for the heat (q) absorbed is

q = mCΔT

We can solve this equation to get

ΔT = q/(mC)

q = 5.49 × 10⁵ J; m = 3030 g; C = 4.184 J·°C⁻¹g⁻¹

∴ ΔT = 5.49 × 10⁵ J/(3030 g × 4.184 J·°C⁻¹g⁻¹) = 43.30 °C

Step 2. Calculate the initial temperature

ΔT = T_f – T_i = 100°C – T_i = 43.30 °C

T_i = 100 °C – 43.30 °C = 56.7 °C

Hey there!

Consider 100 g of solution:

Mass of NaCl = 3.50% of mass of seawater

( 3.50 / 100 ) * 100 => 3.50 g

Number of moles as shown below:

Molar mass NaCl = 58.44 g/mol

n = Mass / molar mass

n = 3.50 / 58.44 => 0.059 moles of NaCl

Mass of sweater:

Mass of solution -  Mass of NaCl

100 -  3.50 = 96.5 g

96.5 g in Kg :

96.5 / 1000 => 0.0965 Kg

Therefore ,calculate molality  by using  the  following formula:

molality =  number of moles  of solute / mass of solution

molality = 0.059 / 0.0965

molality = 0.61 m

Hope That helps!

Answer:The correct answer is option C.

Explanation:

Chemical property of the substance is a property which is observed in a chemical reaction during which identity or composition of the substance changes.

Iron when exposed to air ,react with atmospheric oxygen to from ferric oxide which is a reddish brown in color.Also termed as Rust.

[tex]Fe(s)+O_2(g)\righhtarrow Fe_2O_3(s)(\text{Reddish brown})[/tex]

Hence, the correct answer is option C.

Answer:

The correct answer is option C.

Explanation:

Chemical property is defined as the property of a substance which is observed during a reaction where the chemical composition identity of the substance gets changed.

For Example: reactivity , toxicity etc.

Physical property is defined as the property which can be measured and whose value describes the state of physical system. For Example: State, density etc.

The chemical property observed by the the student is that iron rusts when exposed to air. The oxygen present in the air reacts with iron to form reddish brown compound named rust.

[tex]4Fe(s)+3O_2(g)\rightarrow 2Fe_2O_3(s)[/tex]

Here, iron's reactivity is observed which is a chemical property of the iron.

Where mass ,  density and being a electricity conductor are physical properties.

In chlorine gas, two pairs of valence electrons the atoms share and a non- polar covalent bond is formed.

Covalent bond is defined as a type of bond which is formed by the mutual sharing of electrons to form electron pairs between the two atoms.These electron pairs are called as bonding pairs or shared pair of electrons.

Due to the sharing of valence electrons , the atoms are able to achieve a stable electronic configuration . Covalent bonding involves many types of interactions like σ bonding,π bonding ,metal-to-metal bonding ,etc.

Sigma bonds are the strongest covalent bonds while the pi bonds are weaker covalent bonds .Covalent bonds are affected by electronegativities of the atoms present in the molecules.Compounds having covalent bonds have lower melting points as compared to those with ionic bonds.

Learn more about covalent bond,here:

https://brainly.com/question/19382448

#SPJ6

The answer is condensation.

Have a great day :)

The equation we need to use to solve this is: c=λν

c is the speed of light (2.998 x 10^8 m/s)

λ is the wavelength, which we're gonna solve for

ν is the frequency ( 2.4 x 10^14 Hz )

First, plug in the values we were given into the equation

2.998 x 10^8 m/s= (λ)(2.4 x 10^14 Hz)

Next, divide both sides of the equation by 2.4 x 10^14 Hz to solve for the wavelength (λ)

λ= 1.249166667 x 10^-6 m

Round to 2 significant figures

λ= 1.2 x 10^-6 m

Steps:

Mw = w * R * T / p * V

T = 88 + 273 => 361 K

p = 975 mmHg in atm :

1 atm  = 760 mmHg

975 mmg / 760 mmHg =>  1.28 atm

Therefore:

= 0.827 * 0.0821 * 361 /  1.28 * 0.270

=  24.51 / 0.3456

molar mass =  70.92 g/mol

Answer:

Ozone layer AKA ozone shield

Explanation:

I did this test too! :)

pretty sure its d since its one less layer of our atmosphere but I haven't learned this yet I'm just using common sense

Answer:

Increased exposure to radiation may cause skin ailments.

Hope this helps (;

Answer: phase :option D

Particle :option C

Element : option B

Atom : option A

Explanation:

Answer:

Atom- the basic unit of an element

Element- a substance that cannot be broken down into a simpler substance

Particle- a tiny piece of matter

Phase-  a unique form of matter in which it can exist

Explanation:

I just ahd this on my quiz, swear its correct

I think A is the correct answer but i am not positive

Answer: For red color firework we will use combination of strontium carbonate with lithium carbonate and for purple color we will use combination of strontium salts with copper salts.

Explanation:

There are various metallic salts which on performing flame test imparts characteristic color to the flame and this color is due to presence metal ions.

Color seen during the fireworks are mainly due to the presence of the metal ions present in the material from which the firework is made.

for example : strontium carbonate on flame test imparts bright red color to the flame where as barium chloride imparts green color to the flame.

The combinations of compounds are:

For red color firework we will use the combination of strontium carbonate with lithium carbonate because  combination strontium and lithium ions both imparts red color to the flame.

For purple color we will use the combination of strontium salts with copper salts because combination of strontium and copper ions imparts purple color to the flame.

Is their any specific options..?

Your question is subjective and depends on the context, individual preferences, and the methods available. The choice of method often depends on efficiency, ease of use, and the information at hand.

The question you asked, 'Which method is more convenient for you to use?' is subjective and depends on the individual's preferences, the situation, and the options available. As a tutor, it's difficult to provide a specific answer without knowing the context or the methods being referred to. But in general, the choice of method often depends on factors such as efficiency, ease of use, and the information you have at hand. It's essential to evaluate all of these factors before making a decision on the most convenient method to use.

https://brainly.com/question/3880185

#SPJ12

Hello!

Explanation:

↓↓↓↓↓↓↓

Density is the amount of mass in a given volume. It's a derived unit of measure. It is equal to mass divided by volume. It's measured in units such as grams per cubic centimeter and grams per milliliter. Density is the ratio of mass to volume. Density is a physical property of an object. It is degree of compactness of a substances. Relative density is used to separate solids, liquids, and gases. The gas in the container rises to the top because it has the least density. The liquids separate into individual layers based on their relative densities. The least dense liquid is on top. The most dense liquid is on bottom. The solids sink to the bottom of the container because they have the greatest density.

Hope this helps!

Thank you for posting your question at here on Brainly.

-Charlie

Answer:

The density of a substance is the relationship between the mass of the substance and how much space it takes up (volume). The mass of atoms, their size, and how they are arranged determine the density of a substance. Density equals the mass of the substance divided by its volume; D = m/v.

Explanation:

Try the third option

Answer: Helps visualize feeding relationships in nature

Explanation:

A food web in nature is a interconnection of food chains. In the food chains the food is distributed among various organisms, when organism is consumed by the another.

A scientific model is a kind of simulation that can be used to mimic the natural processes occurring in nature. These can be useful in learning, understanding and demonstrating the natural process.

Among the options given,  Helps visualize feeding relationships in nature is the correct option. This will help in determining how food chains are related in a food web depending upon the feeding relationship between the organisms.  

This would be the downward movement of water. It begins flowing and continues in a downward movement moving throughout,

When the water vapor condenses into larger droplets in the clouds, the formation of rain occurs. The precipitation that flows into river, lakes, and streams is called the rain.

The droplets of water which are condensed as a result of the evaporation is defined as the rain. The formation of clouds takes place during the water cycle. Rain is also called the precipitation. This flows in to all water bodies like river, lakes, etc.

The hot air containing water molecules from different places rises above the ground level and after reaching a particular height it will expands and cools. The process in which the droplets of water changes into water vapor is called the condensation.

The cluster of water droplets combine together to form heavy water masses. When they grow big, they fall down into the atmosphere as rain. They are precipitations. These may be in the form of snow, hail, etc.

Thus the precipitation that flows into river, lakes, and streams is the rain.

To know more about precipitation, visit;

https://brainly.com/question/19664726

#SPJ6

Answer: The correct option is B.

Explanation: All the given reactions are a type of single displacement reactions.

Single displacement reactions are defined as the reactions in which a more reactive metal displaces a less reactive metal in a chemical reaction.

General equation for these reactions is:

[tex]AB+C\rightarrow CB+A[/tex]

For the given reactions, we will use the reactivity series. The metal which lies above in the reactivity series will easily displace the metal which lies below in the reactivity series.

Option A: For this reaction, zinc lies below aluminium in the reactivity series. Hence, zinc will not be able to displace aluminium in the chemical reaction.

Option B: For this reaction, Sodium is more reactive than calcium as it lies above in the reactivity series. Hence, sodium will easily displace calcium in the given chemical reaction.

Reaction follows:

[tex]CaBr_2+2Na\rightarrow 2NaBr+Ca[/tex]

Option C: For this reaction, hydrogen lies below magnesium in the reactivity series. Hence, hydrogen will not be able to displace magnesium in the chemical reaction.

Option D: For this reaction, Calcium lies below barium in the reactivity series. Hence, calcium will not be able to displace barium in the chemical reaction.

Option E: For this reaction, barium lies below lithium in the reactivity series. Hence, barium will not be able to displace lithium in the chemical reaction.

Reactivity series is attached below.

Answer : The reaction form products that are more stable than the reactants will be:

(B) [tex]CaBr_2+2Na\rightarrow 2NaBr+Ca[/tex]

Explanation :

Single displacement reactions : It is defined as the reactions in which a more reactive metal displaces a less reactive metal in a chemical reaction.

The general equation is:

[tex]AB+C\rightarrow CB+A[/tex]

According to the reactivity series, the metal which lies above in the reactivity series will easily displace the metal which lies below in the reactivity series.

(A) [tex]2AlBr_3+3Zn\rightarrow 3ZnBr_2+2Al[/tex]

In this reaction, zinc is less reactive than aluminum as it lies below in the reactivity series. Hence, zinc will not be able to displace aluminium in the chemical reaction. This reaction will not takes place.

(B) [tex]CaBr_2+2Na\rightarrow 2NaBr+Ca[/tex]

In this reaction, sodium is more reactive than calcium as it lies above in the reactivity series. Hence, sodium will easily displace calcium in the given chemical reaction.

(C) [tex]MgBr_2+H_2\rightarrow 2HBr+Mg[/tex]

In this reaction, hydrogen is less reactive than magnesium as it lies below in the reactivity series. Hence, hydrogen will not be able to displace magnesium in the chemical reaction. This reaction will not takes place.

(D) [tex]BaBr_2+Ca\rightarrow CaBr_2+Ba[/tex]

In this reaction, calcium is less reactive than barium as it lies below in the reactivity series. Hence, calcium will not be able to displace barium in the chemical reaction. This reaction will not takes place.

(E) [tex]2LiBr+Ba\rightarrow BaBr_2+2Li[/tex]

In this reaction, barium is less reactive than lithium as it lies below in the reactivity series. Hence, barium will not be able to displace lithium in the chemical reaction. This reaction will not takes place.

One Mn atom contains 5 electrons in it's 3d subshell.

Mn atom has [tex]$\boxed5$[/tex] electrons in its 3d subshell.

Further explanation:  

The electronic configuration is the distribution of electrons of an atom in the atomic orbitals. There are two states for an electron: ground as well as the excited state. The configuration of the atom in the lowest possible energy levels is called the ground-state electronic configuration. When an electron jumps from the stable ground state to some higher level, that state is called the excited state and the electronic configuration corresponding to this state is known as the excited-state half-filled configuration.

The filling of electrons in different energy levels or orbitals is done in accordance with the following three rules.

1. Aufbau principle: The principle states that the electrons are filled in various orbitals in the increasing order of their energies as follows:

1s<2s<2p<3s<3p<4s<3d<4p<5s<4d<5p<6s<4f<5d<6p<7s<5f<6d<7p

2. Hund’s rule: Electron pairing will not start until each orbital is singly occupied.

3. Pauli’s exclusion principle: According to this principle, all the four quantum numbers [tex]$$\left({n,\;l,\;{m_l},\;{m_s}}\right)$$[/tex] for any two electrons can never be the same. In an orbital, the spin of two electrons has to be different. If one electron has the clockwise spin, the other would have the anticlockwise spin and vice-versa.

Manganese is a transition metal of the first transition series. The atomic number of Mn is 25. Its electronic configuration is [tex]$$\left[{{\text{Ar}}}\right]\;3{d^5}4{s^2}$$[/tex] . It has half-filled d-subshell. (Refer to the attached image). So the total number of electrons in 3d subshell of Mn is 5.

Learn more:

1. Determine the ion with configuration [tex]$$\left[{{\text{Ar}}}\right]\;3{d^2}$$[/tex] : https://brainly.com/question/7599542

2. Identification of element which has electron configuration [tex]$$1{s^2}2{s^2}2{p^2}3{s^1}$$[/tex] : https://brainly.com/question/9616334

Answer details:

Grade: High School

Subject: Chemistry    

Chapter: Electronic configuration of the elements

Keywords: Mn, electrons, 3d subshell, 5 electrons, transition metal, 25, transition series, half-filled, aufau principle, Pauli’s exclusion principle, Hund’s rule.

The chemical formula for the compound magnesium perchlorate is Mg(ClO₄)₂

Magnesium perchlorate or Mg(ClO₄)₂ is an ionic compound.

Perchlorate here is an anion which is represented by ClO₄⁻. Perchlorate is a polyatiomic anion, where one Cl atom is bonded to four O atoms.

The magnesium cation is represented by Mg²⁺

So one Mg²⁺ cation combines with two ClO₄⁻ anion to form one molecule of Mg(ClO₄)₂

Answer: Mg(ClO₄)₂

Explanation: Correct on PLATO.

The number of protons in the nucleus always varies among atoms of different elements.

Every element has a different number of protons than every other element.

0.15mg = 0.00015g

Na =22g/mol

Cl= 35g/mol

35g/mol + 22g/mol = 57g/mol

0.00015g * 1 mol/ 57 g =2.63 * 10⁻⁶

0.00015g * 1 mol/ 57 g * NA/1mol = 2.63 * 10⁻⁶ NA

2.63 * 10⁻⁶ * 6.02 * 10²³ = 15.8326 * 10¹⁷

Answer:

2.56×10^-6 moles

Explanation:

Number of formula units is the same as the number if moles of NaCl present.

Number of moles= mass/ molar mass

Molar mass of NaCl= (23+35.5)= 58.5gmol-1

Given mass of NaCl= 0.15×10^-3g

Number of moles= 0.15×10^-3/58.5

Number of moles = 2.56×10^-6 moles

The first basic metal on the periodic table is lithium.

The first basic metal on the periodic table is lithium. It is part of Group 1, which is known as the alkali metals. Alkali metals are very reactive and form basic (alkaline) solutions when they react with water.

https://brainly.com/question/30421635

#SPJ12

The first basic metal on the periodic table is lithium, part of the alkali metals in group 1 of the periodic table. These metals are known for their reactivity, forming ions to create ionic compounds which are usually soluble in water.

The first basic metal on the periodic table is lithium. It's part of the alkali metals which constitute group 1 of the periodic table. The other alkali metals are sodium, potassium, rubidium, cesium, and francium. Despite hydrogen also being in group 1, it is not considered a metal but a nonmetal.

These alkali metals are known for their high reactivity. They readily form ions with a charge of 1+ to create ionic compounds, which usually dissolve in water. In addition, they react vigorously with water to produce hydrogen gas and a basic solution of the metal hydroxide, hence justifying the name alkali metal.

Many of these elements may not occur naturally in an uncombined state because they can readily react with water and oxygen in the air. Yet, when isolated from their naturally occurring minerals, they react very slowly with air due to the formation of a protective nonreactive film coating also known as passivation.

https://brainly.com/question/5063184

#SPJ12

ganan electrones debido a que gracias a la regla del octeto alcanzan estabilidad de los gases nobles.

es la C

In chemical reactions between metals and nonmetals metals lose electrons and become positively charged ions or cations through a process called ionic bonding. An example of this process is when Sodium (Na) loses an electron to become Na+ and combines with Chlorine (Cl) to form Sodium Chloride (NaCl).

When metals like Na (Sodium) combine with nonmetals such as Cl (Chlorine), the metals lose electrons and become positively charged ions. This happens due to the process of ionic bonding where electrons are transferred from the metal atom to the nonmetal atom. In this case, Sodium loses one electron to become a cation (Na+), and Chlorine gains this electron to become an anion (Cl-). This difference in electric charge holds the atoms together, thus creating an ionic compound namely Sodium Chloride (NaCl).

https://brainly.com/question/11527546

#SPJ3

The three main ideas behind capitalism as defined by Adam Smith are "competition, self interest, and laissez-faire," since Smith was a heavy proponent of the "invisible hand of the market".

D.  The number of electrons equals the atomic number for a neutral element.  Each number after the letter refers to the number of electrons in that shell.  So for D, 2+2+6+2+6+2 = 20 electrons, which is equal to the atomic number.

D. 1s2 2s2 2p6 3s2 3p6 4s2

Hope this helps!

Answer:

B

Explanation:

30.97 g/mol

B. 30.97 g/mol. Molar mass of phosphorus (P) = 30.97 g/mol. So, the correct answer is B. 30.97 g/mol.

The molar mass of an element is the mass of one mole of atoms of that element, expressed in grams per mole (g/mol). To find the molar mass of phosphorus (P), we look at the periodic table to find the atomic mass of phosphorus.

The atomic mass of phosphorus (P) is approximately 30.97 atomic mass units (amu).

Since 1 mole of any element contains Avogadro's number of atoms (6.022 × 10²³), the molar mass of phosphorus (P) is equal to its atomic mass in grams:

Molar mass of phosphorus (P) = 30.97 g/mol

So, the correct answer is B. 30.97 g/mol.

To know more about phosphorus:

https://brainly.com/question/30143602

#SPJ6

The other change that will occur in the bottle is that A. The air pressure will increase.

If volume changes in a closed container, while temeprature remains constant, the phenomenon is described by Boyle's Law:

[tex]P1*V1=P2*V2[/tex]

Let's give some arbitrary values to these variables:

P1= 1 atm

V1= 2 L

P2= ?

V2= 1 L

Calculating the final pressure (P2):

[tex]P2=\frac{P1*V1}{V2}=\frac{1 atm*2 L}{1 L}=2 atm[/tex]

So, the final pressure is higher than the initial pressure (P2>P1). That means that Pressure and Volume are inversely proportional.

Have a nice day!