what are the harmful effects of water pollution​

Answer:A

Explanation:

Your muscular system is at work

There are 2 grams remain

Given

t1/2 = 30 years

t = 170 years

No = 100 g

Required

Remaining sample

Solution

General formulas used in decay:  

[tex]\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{t/t\frac{1}{2} }}}[/tex]

Input the value :

[tex]\tt Nt=100.\dfrac{1}{2}^{170/30}\\\\Nt=1.969\approx 2~grams[/tex]

Answer: [tex]Fe^{2+}[/tex] is the reducing agent

Explanation:

Oxidation reaction : When there is an increase in oxidation state number.

Reduction reaction : when there is a decrease in oxidation state number.

[tex]5Fe^{2+}(aq)+MnO_4^-(aq)+8H^+(aq)\rightarrow 5Fe^{3+}(aq)+Mn^{2+}(aq) +4H_2O(l)[/tex]

Fe has undergone oxidation, as its oxidation state is changing from+2 to +3.

Mn has undergone reduction, as its oxidation state is changing from +7 to +2.

The chemical agent which itself get oxidized and reduce others is called reducing agent.  [tex]Fe^{2+}[/tex]  is a reducing agent.

The chemical agent which itself get reduced and oxidize others is called oxidizing agent. [tex]MnO_4^-[/tex] is an oxidizing agent.

.

Answer:

C2H5OH(l)+3O2(g)⟶2CO2+3H2O(l)

Explanation:

The balanced equation for the combustion of ethanol will be

[tex]C_{2}H_{5}OH+3O_{2}------- > 2CO_{2}+3H_{2}O[/tex]. According to this carbon dioxide and water will be the product.

Combustion is a chemical process during which a material reacts quickly with oxygen and generates heat.

The original substance is referred to as the fuel, and the supplier of oxygen is referred to as the oxidizer. The fuel can be solid, liquid, or gas, but it is usually a liquid for airplane propulsion.

Combustion is a chemical reaction between two or more substances, usually involving oxygen, that produces light and heat in the form of a flame.

The products of complete ethanol combustion are carbon dioxide and water, as well as the start releasing of light and heat.

The equation will be:

[tex]C_{2}H_{5}OH+3O_{2}------- > 2CO_{2}+3H_{2}O[/tex]

Thus, in this way, the combustion of ethanol occurs.

For more details regarding combustion, visit:

https://brainly.com/question/15117038

#SPJ2

Answer: Boiling point, because it can be observed by altering the state of the substance

Explanation:

Physical property is defined as the property of a substance which becomes evident during physical change in which there is alteration in shape, size etc. No new substance gets formed during physical change. Example: Melting point

Chemical property is defined as the property of a substance which becomes evident during chemical change in which a change in chemical composition takes place. A new substance is formed in these reactions. Example: Reactivity with other substances

Thus Boiling point is a propertywhich can be examined without altering the composition, because it can be observed by altering the state of the substance

Answer:

B

Explanation:

uncontrolled energy damage the body

Answer: causes destruction

Explanation:

Answer:

Phosphorus P (s)

Neon Ne (g)

Chlorine Cl (g)

Explanation:

Iron: Fe(s) - The (s) denotes that iron is in its solid state.

Phosphorus: P(s) - The (s) indicates that phosphorus is in its solid state.

Neon: Ne(g) - The (g) signifies that neon is in its gaseous state.

Chlorine: Cl₂(g) - The (g) indicates that chlorine exists as a diatomic gas, with the formula Cl2, in its standard state.

Iron (Fe):

Iron is a chemical element commonly found in its solid state under standard conditions. The chemical symbol for iron is Fe, which is derived from the Latin word "ferrum." Iron is a lustrous, silvery-gray metal and is known for its strength and ability to be magnetized. In its standard state, iron exists as a solid, denoted by the (s) symbol. Therefore, the complete chemical formula for iron in its standard state is Fe(s).

Phosphorus (P):

Phosphorus is an element that exists in various forms, with the most common form being a solid known as white phosphorus. Under standard conditions, white phosphorus is the most stable and prevalent form. It is a waxy, white-to-yellowish solid that is highly reactive and combustible. The chemical symbol for phosphorus is P, and it is represented by the (s) symbol to indicate its solid state. Therefore, the complete chemical formula for phosphorus in its standard state is P(s).

Neon (Ne):

Neon is a chemical element that exists as a gas under standard conditions. It is a noble gas and is known for its bright red-orange glow when used in signs and lighting. Neon is chemically inert, meaning it does not readily react with other substances. The chemical symbol for neon is Ne, and it is represented by the (g) symbol to indicate its gaseous state. Therefore, the complete chemical formula for neon in its standard state is Ne(g).

Chlorine (Cl):

Chlorine is a halogen element that exists as a diatomic gas under standard conditions. It is a highly reactive and corrosive substance with a yellowish-green color and a pungent odor. Chlorine exists as a molecule with two chlorine atoms bonded together, forming Cl₂. The (g) symbol is used to indicate that chlorine exists as a gas. Therefore, the complete chemical formula for chlorine in its standard state is Cl₂(g).

Learn more about chemical formula from the link given below.

https://brainly.com/question/32018188

#SPJ2

Heat required to raise temperature : 224.02 J

Given

mass CCl4 = 4.66 g

Δt= 76.8 - 20.9 =55.9 °C

c = The specific heat capacity of CCl4 = 0.856 J/g◦C.

Required

Heat /energy required

Solution

Heat can be formulated

Q=m.c.Δt

[tex]\tt Q=4.66\times 0.86\times 55.9\\\\Q=224.02~J[/tex]

Answer:

Since the 3s if now full we'll move to the 3p where we'll place the remaining five electrons. Therefore the Chlorine electron configuration will be 1s22s22p63s23p5. The configuration notation provides an easy way for scientists to write and communicate how electrons are arranged around the nucleus of an atom.

Answer:

This is because, Kelvins and Celcius degrees both agree at fixed points i.e; the lower fixed point and upper

Answer:

The formula for the compound isB6Br7

Answer:

Q1 D

Explanation:

Q2 C

Answer: Strong and Weak Acids

Explanation:

Acids, also known as electrolytes, are compounds that break down into cations (positively charged ions) and anions when dissolved in water (negatively charged ions). Solid Electrolytes (Acids) fully ionize,

Whereas weak electrolytes (acids) only partly ionize.

Answer:

5.38 g of CO.

Explanation:

From the question given above, the following data were obtained:

Volume of CO = 4.3 L

Mass of CO =?

Next, we shall determine the number of mole of CO that occupied 4.3 L at STP. This can be obtained as follow:

Recall = 1 mole of any gas occupy 22.4 L at STP.

1 mole of CO occupied 22.4 L at STP.

Therefore, Xmol of CO will occupy 4.3 L at STP i.e

Xmol of CO = 4.3 / 22.4

Xmol of CO = 0.192 mole.

Thus, 0.192 mole of CO occupy 4.3 L at STP.

Finally, we shall determine the mass of CO as follow:

Mole of CO = 0.192 mole.

Molar mass of CO = 12 + 16 = 28 g/mol

Mass of CO =?

Mole = mass /Molar mass

0.192 = mass of CO / 28

Cross multiply

Mass of CO = 0.192 × 28

Mass of CO = 5.38 g.

Therefore, 5.38 g of CO occupied 4.3 L at STP.

Answer:

False

Explanation:

The correct answer would be false.

If a chemical is ingested while working in the lab, the correct thing to do would be to contact the lab instructor right away as eating or drinking of any kind is prohibited in the laboratory.

While drinking milk may help in some cases depending on the nature and amount of the chemical ingested, only the lab instructor has the technical know-how to analyze the situation and administer first aids. Milk has the capacity to act as a buffer in some cases pending the time the victim would be able to get adequate medical attention.

Answer:

c. I and Ill

Explanation:

SN1 mechanism is a unimolecular nucleophillic substitution reaction mechanism. "Unimolecular" implies that only one molecule is involved in the rate determining step and that is the alkyl halide. The rate determining step of SN1 reaction is the formation of a carbocation which subsequently reacts with a nucleophile in the fast step.

SN1 reactions occur mostly with tertiary alkyl halides due to sterric reasons. SN2 mechanism involves a crowded transition state because it is a concerted reaction mechanism. This is not possible in a tertiary alkyl halide due to the presence of bulky groups around the tertiary carbon atom hence tertiary alkyl halides do not undergo nucleophilic reaction by SN2 mechanism.

Secondly, polar solvents aid in the ionization of the alkyl halide thus assisting in the formation of the carbocation which participates in the second step of the reaction.

Answer:

a)215000

b) 3.2

c) 2.08

d) 27439.74

Explanation:

Significant figures:

When we add or subtract the values the number of significant figures after decimal in result must be equal to the given measurement having less number of decimal places.

b) 5.45 -2.3

3.2

d) 14.98 + 27,340 + 84.7593

27439.74

When we multiply or divide the values the number of significant figures must be equal to the less number of significant figures in given value.

a) 628 × 342

214776

we will round off this value into 3 significant figures.

215000

c) 28.0/13.483

2.08

Answer:

it is true because i just took the test and i did research on it

Explanation:

i study this and because i did research

Answer:

trueeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

Explanation: eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

The less soluble salt : PbCl₂

Given

0.1 M NaCl

Required

The less soluble salt

Solution

If we see from the answer option, the salt that is more difficult to dissolve in NaCl is PbCl₂ because it has the same ion (Cl)

When PbCl₂ is dissolved in water, ionization will occur

PbCl₂ ⇒ Pb²⁺+ 2Cl⁻

So, when dissolved in NaCl, NaCl itself will be ionized

NaCl ⇒ Na⁺ + Cl⁻

Based on the principle of equilibrium, the addition of an ion (one of the ions is enlarged), the reaction will shift towards the ion that was not added. In addition to this Cl ion, the reaction will shift to the left so that the solubility of PbCl₂ will decrease (the reaction to the right decreases)

Answer:

Energy released by 1 g of U-235 = 7.603 * 10¹⁰ J

Explanation:

Uranium-235, U-235 undergoes neutron-induced fission to give the following products:

1 neutron + ²³⁵U --> ¹⁴¹Ba + ⁹²Kr + 3 neutrons

Masses of reactants and products:

neutron = 1.009 amu, uranium-235 = 235.044 amu, Ba-141 = 140.910 amu, Kr-92 = 91.910 amu

mass defect = mass of reactants - mass of products

mass defect = (235.044 + 1.009) - (140.910 + 91.910 + 3 * 1.009)

mass defect = 236.053 - 235.847 = 0.206 amu

1 amu = 1.6 * 10⁻²⁷ kg

Using E = mc²

E = 0.206 * 1.6* 10⁻²⁷ kg * (3 * 10⁸ m/s)² = 2.966 * 10⁻¹¹ J

therefore, 1 atom of U-235 releases 2.966 * 10⁻¹¹ J of energy

energy released by 1 g of U-235 can be calculated as follows:

1 mole or 253 g  of U-235 contains 6.02 * 10³ atoms

1 g of U-235 will contain 6.02 * 10³/235 = 2.563 * 10²¹ atoms

Energy released by 1 g of U-235 = 2.563 * 10²¹ * 2.966 * 10⁻¹¹ J = 7.603 * 10¹⁰ J

Answer:

In its astrobiology roadmap, NASA has defined the principal habitability criteria as "extended regions of liquid water, conditions favorable for the assembly of complex organic molecules, and energy sources to sustain metabolism". In August 2018, researchers reported that water worlds could support life.

Answer:

Atomic Number

Explanation:

The number of protons an atom has is unique to that element. The number of protons is noted as the atomic number for that element on the periodic table.

Answer:

IV

Explanation:

The complete question is shown in the image attached.

Let us call to mind the fact  that the SN1 mechanism involves the formation of carbocation in the rate determining step. The order of stability of cabocations is; tertiary > secondary > primary > methyl.

Hence, a tertiary alkyl halide is more likely to undergo nucleophilic substitution reaction by SN1 mechanism since it forms a more stable cabocation in the rate determining step.

Structure IV is a tertiary alkyl halide, hence it is more likely to undergo nucleophilic  substitution reaction by SN1 mechanism.

The mass of the Pbl2 : 1308.87

Given

18.2 mL of a 0.156 M Pb(NO3)2

26.2 mL of a 0.274 M KI

Reaction

Pb(NO3)2 (aq) + 2 KI (aq) - Pbl2 (s) + 2 KNO3

Required

the mass of the Pbl2

Solution

mol Pb(NO3)2 = 18.2 x 0.156 = 2.8392 mlmol

mol KI = 26.2 x 0.274 =7.1788 mol

Limiting reactant Pb(NO3)2(smaller ratio of mol : reaction coeffiecient)

mol Pbl2 based on limiting reactant (Pb(NO3)2)

From equation, mol ratio of Pb(NO3)2 : Pbl2 = 1 : 1, so mol Pbl2=mol Pb(NO3)2=2.8392

Mass Pb(NO3)2 :

[tex]\tt mass=mol\times MW\\\\mass=2.8392\times 461\\\\mass=1308.87~grams[/tex]

Answer:

True

Explanation:

We know that the zero-point-energy of a C-D system is quite lower than the zero point energy of the C-H bond so the C-D bond is stronger.

Kinetic isotope effect refers to the change in the rate of reaction owing to a change of one of the atoms of the reactants by replacing it with one of its isotopes.

Since we know that the C-D bond is stronger than the C-H bond, when we replace hydrogen with deuterium in a reaction's rate determining step we experience a little lag in the rate of reaction. This is referred to as the kinetic isotope effect in physical organic chemistry.

Answer:

A) An electrolytic cell, because it absorbs energy.

Explanation:

The major difference between an electrolytic cell and a voltaic cell is that, in an electrolytic cell, there must be input of energy from outside (a cell) to drive the non spontaneous reaction while in a voltaic cell, the reaction proceeds on its own and releases energy which could be harnessed to do work.

Hence, considering the equation; 2H2O+ electricity → 2H2 + O2 , energy is supplied as electricity in order for the process to take place. This is an example of an electrolytic cell.

Answer:

Q =  -1045 J

Explanation:

Given data:

Mass of water = 5.00 g

Initial temperature = 348.0 K

Final temperature = 298.0 K

Heat given off = ?

Solution:

Specific heat capacity:

It is the amount of heat required to raise the temperature of one gram of substance by one degree.

Specific heat capacity of water is 4.18 J/g.K

Formula:

Q = m.c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

ΔT = 298.0 K - 348.0 K

ΔT = - 50 K

Q = 5.0 g ×4.18 J/g.K× - 50 K

Q =  -1045 J