15. What is the name of the part of a cell that allows molecules in, such as glucose and oxygen?
a. Cell wall
b. Ribosome
c. mitochondria
d. Cell membrane
​

Answer:

d. Because those chemicals are easily made when CO2 reacts with water, forming H2CO3 (via carbonic anhydrase

The pairs of substances form a buffer system for human blood is carbonic acid (H₂CO₃) and bicarbonate anion (HCO₃⁻)  , Option D

A buffer is a  combination of a weak acid (or base) and a salt that contains the conjugate of that weak acid or base.

A buffer solution is added to maintain the pH of any solution

The buffer  of carbonic acid (H₂CO₃) and bicarbonate anion (HCO₃⁻)  is used to maintain the balance of acid and base in the body.

It is used to maintain the pH level of the body between 7.35 and 7.45 , as the pH level higher than 7.8 and lower than 6.8 can lead to death.

Therefore the pairs of substances form a buffer system for human blood is carbonic acid (H₂CO₃) and bicarbonate anion (HCO₃⁻)  , Option D

To know more about Buffer Solution

https://brainly.com/question/24262133

#SPJ2

Answer:

B.

Solar energy is converted into chemical potential energy, which is found in the products like glucose.

Explanation:

According to photosynthesis phenomena ,the statement which compares energy transformations in ecosystem  within photosynthetic organisms is statement B.

It is defined as a process by which plants and other photosynthetic organisms convert the light energy in to chemical energy  through the process of cellular respiration.

Some of the energy which is converted  is stored in molecules of carbohydrates like sugar and starches  which are made up of from carbon dioxide and water . Photosynthetic organisms which can perform photosynthesis  are algae and cyanobacteria. Photosynthesis is largely responsible for producing and maintaining the content of oxygen in earth's atmosphere.

The process begins with proteins absorbing light energy  which are called reaction centers and contain a green pigment which is called chlorophyll . In plants ,these pigments are present inside organelles called chloroplasts while in bacteria they are present in plasma membrane.

Learn more about photosynthesis,here:

https://brainly.com/question/1757345

#SPJ5

Answer:

A double displacement is a type of chemical reaction that in which the reactant ions exchange places to form new products

Explanation:

I took the quiz

Answer:

When two different atoms or groups of atoms are exchanged, then it is a double displacement reaction.

Answer:

B

Explanation:

Answer:

Initial velocity (u) = 0 m/s

Final velocity (v) = 60 m/s

Time (t) = 7 sec

Acceleration (a) = ?

a = (v-u)/t

a = (60-0)/7

a = 60/7

a = 8.57 m/s²

Answer:

Cohesion

Explanation:

D. you're welcome

One of water's most distinctive properties is cohesion—that is, the tendency of water molecules to "stick" to one another. In plants, this cohesion results in columns of water that stretch through the plant's xylem (the vascular tissue responsible for the transport of water), from the roots all the way to the leaves.

Answer:

The growing human population is putting increasing demands on natural resources.

Explanation:

In an ecosystem, the most important reason for people to carefully manage natural resources is that the  growing human population is putting increasing demands on natural resources.

Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.

Energy enters the ecosystem through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.

Learn more about ecosystem,here:

https://brainly.com/question/13979184

#SPJ6

Answer:

34176.5 torr

Explanation:

It is given that :

Initial pressure, [tex]$P_1 = 830$[/tex] torr

Initial volume, [tex]$V_1 = 650 \ cm^3$[/tex]

Initial temperature,   [tex]$T_1 = 85^\circ C$[/tex]

Final volume,  [tex]$V_2 = 65 \ cm^3$[/tex]

Final temperature,   [tex]$T_2 = 350^\circ C$[/tex]

Therefore, using the combined gas laws, we can write :

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

Substituting the values, we get

[tex]$\frac{830 \times 650}{85}=\frac{P_2\times 65}{350}$[/tex]

[tex]$P_2 = \frac{830 \times 650 \times 350}{85 \times 65}$[/tex]

    = 34176.5 torr

So the new pressure is 34176.5 torr.

Answer: 130g  , 40g ,  70g

Explanation:

Answer:

See Explanation

Explanation:

A decreasing temperature indicates that the dissolution process for the ammonium chloride requires input of energy from surroundings. That is, the process is essentially 2 parts => system (object of interest - NH₄Cl) and the surroundings (everything else - solvent - H₂O). The surroundings (water) solvent is showing a measured decrease in temperature or loss of energy (exothermic to surroundings) which flows into the system (NH₄Cl) and effects dissolution of salt into solution (endothermic to system).

Answer:

vapor pressure, atmospheric pressure

Explanation:

the boiling point of a liquid is the temperature at which its vapor pressure is equal to the pressure of the gas above it.

(I'm not too sure if this is right but I think it is)

Answer: The percent ionization is higher for 0.010 M solution of [tex]HC_2H_3O_2[/tex]

Explanation:

[tex]HC_2H_3O_2\rightarrow H^+C_2H_3O_2^-[/tex]

 cM           0M           0M

[tex]c-c\alpha[/tex]        [tex]c\alpha[/tex]          [tex]c\alpha[/tex]  

So dissociation constant will be:

[tex]K_a=\frac{(c\alpha)^{2}}{c-c\alpha}[/tex]

a) Given c= 0.10 M and [tex]\alpha[/tex] = ?

[tex]K_a=1.8\times 10^{-5}[/tex]

Putting in the values we get:

[tex]1.8\times 10^{-5}=\frac{(0.10\times \alpha)^2}{(0.10-0.10\times \alpha)}[/tex]

[tex](\alpha)=0.013[/tex]

[tex]\%(\alpha)=0.013\times 100=1.3\%[/tex]

b) Given c= 0.010 M and [tex]\alpha[/tex] = ?

[tex]K_a=1.8\times 10^{-5}[/tex]

Putting in the values we get:

[tex]1.8\times 10^{-5}=\frac{(0.010\times \alpha)^2}{(0.010-0.010\times \alpha)}[/tex]

[tex](\alpha)=0.041[/tex]

[tex]\%(\alpha)=0.041\times 100=4.1\%[/tex]

The percent ionization is higher for 0.010 M solution of [tex]HC_2H_3O_2[/tex]

Answer:

L=0.85M

Explanation:

ca3 (po4)

66gX1mol/310.18g=2.2178mol/2.5

Zinc (Zn) has less than 34 protons, 30 to be exact, and is a transition metal in Group 12. Note: it is also called a "post-transition metal."

Answer:10-^7M

Explanation: this is a neutral solution as the [H+] and [OH-] is of same value ie,10-^7M

Explanation:

babe I wish I knew I would tell you

Answer:

Not all men are like this. It depends on how they were raised

Answer:

I believe that it would be copper because copper is all of those things.

Explanation:

Answer:

electroluminescence is a production of light by the flow of electrons, as within certain crystals. An example is at most resataurants with a bright sign that either says open or closed.

Explanation:

Answer:

Explanation:

are you doing your mid term?well i got c

Answer:

D

Explanation:

Compounds 1 and 3 are lonic.Because ionic compounds are composed of oppositely charged ions that are attracted to one another,

they require more energy to melt than covalent bonds. just usign he process of elimination you get rid of A and B becuase covalant compound contaIN same negatively charged particles that contain requrie less energy to melt and since two and four have low melting point its d

Answer: The answer is B 1,3

Answer:

1 mole of magnesium are required to react with 2.0 mol of hydrochloric acid.

Explanation:

The balanced reaction is:

Mg + 2 HCl → MgCl₂ + H₂

The law of conservation of matter states that since no atom can be created or destroyed in a chemical reaction, the number of atoms that are present in the reagents has to be equal to the number of atoms present in the products. That is, the law of conservation of mass implies that the sum total of charges before and after the chemical reaction remains constant.

The relationships between the quantities of reactants consumed and products formed depend directly on this conservation law, and therefore can be determined by an equation that describes them. This equality is called the stoichiometric equation.

In this case, by stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), you have:

Then, 1 mole of magnesium are required to react with 2.0 mol of hydrochloric acid.

Answer:

1 mole of magnesium, Mg

Explanation:

The balanced equation for the reaction is given below:

Mg + 2HCl —> MgCl₂ + H₂

From the balanced equation above,

We can see clearly that 1 mole of Mg requires 2 moles of HCl.

Thus, 1 mole of magnesium, Mg is needed for the reaction.

Answer:

13

Explanation:

proton plus neutron equal to atomic mass

Answer:

A

Explanation:

True igneous rock forms cooling of magma fast on the top

Answer:

The answer is A. True

Explanation:

Answer:

50distance and 10minutes time

Explanation:

because it's the best object

Answer:

Decomposers (either Secondary Consumer or Tertiary Consumer)

Explanation:

Decomposers eat dead materials and break them down into chemical parts. ... They keep the ecosystem free of the bodies of dead animals or carrion. They break down the organic material and recycle it into the ecosystem as nutrients. Vultures, Blowflies, hyenas, crabs, lobsters and eels are examples of scavengers.

Answer:55ml

Explanation: