A formulation for a nebulizer begins its existence at 100 mg/ml of active substance. Ten months later its concentration has fallen to 75 mg/ml. Calculate the drug's half-life and what amount is left after 18 months if the order of the reaction is (a) zero order (b) first order.

This is a false statement. An aquarium is not divided by a membrane that is not permeable to any ion. Such a membrane is called an ion-selective membrane.

If such a membrane were present in the aquarium, the potential difference between the two sides would indeed be 58 mV, according to the Nernst equation. However, in reality, there would be no potential difference because ions would be able to cross the membrane. In fact, many aquariums use ion-selective membranes to maintain a stable environment for their aquatic organisms. The membrane allows for the regulation of ion concentrations and pH levels in the aquarium. So, in summary, the statement is false because an aquarium is not typically divided by a membrane that is impermeable to ions.

To know more about aquarium visit:

https://brainly.com/question/6567948

#SPJ11

Answer:FALSE

Explanation:

Answer:

false, mass is the measure of the corpue attrraction on the heart centre

Answer:

2/3 xX ml of gas

Explanation:

P1V1= P2V2

2 x X= 3 x y

y (new volume)= 2/3 x

0.66 x will be the new volume when the pressure of x mL of gas was increased from 2 ATM to 3 ATM at a constant temperature.

The ideal gas law (PV = nRT) relates to the macroscopic properties of ideal gases. An ideal gas is a gas in which the particles (a) do not attract or repel one another and (b) take up no space (have no volume).

Given:

\(P_1\)= 2 ATM

\(V_1\)= x mL

\(P_2\) =3 ATM

\(V_2\) =?

\(P_1V_1= P_2V_2\)

2 x X= 3 x Y

Y(new volume)= 0.66 x

Hence, 0.66 x will be the new volume when the pressure of x mL of gas was increased from 2 ATM to 3 ATM at a constant temperature.

Learn more about the ideal gas here:

https://brainly.com/question/27691721

#SPJ5

Answer:

D

Explanation:

magnesium always lose 2 electrons

The molecule H₁₂O₆ does not exist in nature. The formula H₁₂O₆ suggests the presence of 12 hydrogen atoms and 6 oxygen atoms.

However, such a configuration is highly unstable and does not conform to the principles of chemical bonding and stability. In a typical molecule of water (H₂O), two hydrogen atoms are bonded to one oxygen atom. The Lewis structure for water would represent this bonding arrangement. Each hydrogen atom contributes one valence electron, and oxygen contributes six valence electrons.

The Lewis structure for water would show two lines (representing covalent bonds) connecting the oxygen atom to each hydrogen atom. Additionally, the oxygen atom would have two lone pairs of electrons (represented by dots) surrounding it. It is important to note that the Lewis structure represents the valence electron arrangement in a molecule and provides insight into its bonding and geometry.

However, the Lewis structure alone may not capture the full 3D shape and molecular properties. In the case of H₁₂O₆, the presence of 12 hydrogen atoms and 6 oxygen atoms is highly unlikely due to the unfavorable electron configuration and excessive charge repulsion.

know more about hydrogen atoms here:

https://brainly.com/question/28499820

#SPJ8

Partial bonding, for example, as part of a resonance hybrid, often results in structures with fractional bond orders.

What is resonance?

Resonance in chemistry, also known as mesomerism, is a means to describe bonding in specific molecules or polyatomic ions by fusing a number of contributing structures into a resonance hybrid according to valence bond theory.

Resonance structure identification guidelines:

Atoms are immobile. Electrons can only be moved in bonds or lone pairs (that are in p orbitals) The system's total fee must not change. A molecule's bonding structure needs to be preserved.

Therefore, Partial bonding, for example, as part of a resonance hybrid, often results in structures with fractional bond orders.

To learn more about resonance

Here: https://brainly.com/question/13741444

#SPJ4

Answer:

The Charpy Impact Test evaluates the impact energy of materials under high strain rates.

The temperature range for which the Charpy impact test is performed for GS52 material is -20°C.

The Charpy Impact Test evaluates the impact energy of materials under high strain rates.

The Charpy Impact Test is typically carried out at low temperature, below the ductile to brittle transition temperature.

The temperature range for which the Charpy impact test is performed for GS52 material is -20°C.

Hence, the Charpy impact strength test is performed at -20°C for GS52 material.

The Charpy Impact Test evaluates the energy absorbed by a standard notched specimen while it is fractured under an impact load. The energy absorbed by the specimen is a measure of its impact strength or toughness under these conditions.

The results of the Charpy Impact Test are expressed in joules (J) or ft-lbf and indicate the amount of energy that the material can absorb before fracturing.

Hence, the Charpy impact strength test is performed at -20°C for GS52 material.

Learn more about Charpy Impact Test , here

https://brainly.com/question/13257047

#SPJ11

Answer :  625 mL of the salt solution with a molarity of 20.0 mol/L can be added to the original solution to create a new solution with a molarity of 5.00 mol/L.

We can use the formula for calculating the molarity of the new solution: M1V1 + M2V2 = M3V3 where, M1 is the molarity of the first solution, V1 is the volume of the first solution, M2 is the molarity of the second solution ,V2 is the volume of the second solution, M3 is the molarity of the final solution and V3 is the volume of the final solution

Now, we will plug in the given values: M1 = 2.50 mol/LV1 = 5.00 LM2 = 20.0 mol/LV2 =  5.00 mol/L, V3 = 5.00 L. We can rearrange the formula to find V2 as  = (M3 V3 - M1 V1) / M2 V2 = (5.00 mol/L x 5.00 L - 2.50 mol/L x 5.00 L)/20.0 mol/LV2 = 0.625 L or 625 mL. So we require  0.625 L or 625 ml salt solution.

Know more about molarity here:

https://brainly.com/question/8732513

#SPJ11

Answer:

You have to change the number of protons in the nucleus. While it is possible, it requires bombarding and putting together elements, which creates high energy particle accelerators.

Answer:

No, there is not because it would form H2 instead of methane if hydrogen bonded with itself.

Explanation:

from the shape of methane which is tetrahedral it's evident there's no hydrogen bond only C-H bond.

The chemical formula of methane is \(CH_4\) but: C. No, there is no bond between any of the hydrogen atoms because it would form \(H_2\) instead of methane if hydrogen bonded with itself.

A chemical bond is defined as the forces of attraction existing between ions, crystals, atoms or molecules and they are mainly responsible for the formation of chemical compounds.

This ultimately implies that, a chemical bond refers to a force holding two or more atoms together and binding ions, crystals, or molecules together, in order to form a chemical compound.

Methane comprises of an atom of carbon and four (4) atoms of hydrogen.

Basically, hydrogen only shares a single (one) valence electron with carbon but not itself (hydrogen atoms) to form methane because of the \(sp^3\) hybridization.

Hence, there is no bond existing between any of the four (4) hydrogen atoms because it would form \(H_2\) instead of methane (\(CH_4\)), if hydrogen bonded with itself.

Read more: https://brainly.com/question/24212500

The molecular formula of the compound is C6H12O6.

1) We know that;

1 mole of CO2 contains 6.02 X 10^23 atoms

x moles of CO2 contains 1.5 X 10^23 atoms

x = 1 mole X  1.5 X 10^23 atoms /6.02 X 10^23 atoms

x = 0.25  moles of CO2

2) 1 mole of pure Al has 27 g

x moles of Al has 5 g

x = 1 mole ×  5 g/ 27 g

x = 0.19 moles

If 1 mole of Al contains 6.02 X 10^23 atoms

0.19 moles of Al contains 0.19 moles  ×  6.02 X 10^23 atoms /1 mole

= 1.14 X 10^23 atoms

3) From 2Na + Cl2 ---> 2NaCl;

2 moles of Na produces 2 moles of NaCl hence 3 moles of Na will also produce 3 moles of NaCl.

4) The molar mass of K2SO4 is obtained from;

2(39) + 32 + 4(16) = 78 + 32 + 64 = 174 g/mol

Now;

Percentage by mass of K = 2(39)/ 174  ×  100/1 = 44.8%

Percentage by mass of S = 32/174 ×  100/1 = 18.4%

Percentage by mass of O = 4(16)/174 ×  100/1 = 36.8%

5) The reaction equation is;

4Al(s) + 3O2(g) ----> 2Al2O3

Total mass present =  162g + 144g = 306 g

Mass percent of Al =  162g/ 306 g ×  100/1 =52.9%

6)

C - 40/12     H -  6.71/1        O - 53.29/16

C - 3.33      H - 6.71            O - 3.33

Dividing through by the lowest ratio

C- 3.33/3.33     H - 6.71/3.33    O - 3.33/3.33

C - 1                  H - 2                 O - 1

The empirical formula is CH2O

Now;

[12 + 2(1) + 16] n = 180.16

30n = 180.16

n = 180.16/30

n = 6

The molecular formula is C6H12O6.

Learn more about molecular formula: https://brainly.com/question/11588623

Answer:

Explanation:

In the scenario that is being described the control group would be the 50 men that have been given the placebo because they are the ones that should not have any effects from the placebo and that is by design. The manipulated variable is the new fat-burning pill because it is the one that the scientists can change and modify to try and achieve the desired results. Lastly, the responding variable are the 50 men who are given the new fat-burning pill because they are the ones that will be responding to the effects of the pill and providing the data needed by the scientists.

Hydrogen bonding is a sort of intermolecular bonding that takes place when a hydrogen atom is covalently bonded to a highly electronegative atom, such as nitrogen, oxygen, or fluorine.

As a result of the electronegativity difference, the hydrogen atom acquires a partial positive charge, whereas the electronegative atom acquires a partial negative charge. Hydrogen bonds are created between these oppositely charged regions and are weaker than covalent bonds but stronger than van der Waals interactions. The presence of a hydrogen bond donor and a hydrogen bond acceptor is necessary for hydrogen bonding to occur.

A hydrogen bond donor is a molecule that has a hydrogen atom bonded to a highly electronegative atom and is capable of forming hydrogen bonds, whereas a hydrogen bond acceptor is a molecule that is capable of forming hydrogen bonds with a donor molecule's hydrogen atom. Out of the provided molecules, the following are capable of acting as hydrogen bond donors: Ammonia (NH3)Ethanol (CH3CH2OH)Water (H2O)Formaldehyde (H2-C=O)

In conclusion, molecules capable of acting as hydrogen bond donors are Ammonia, Ethanol, Water, and Formaldehyde.

To know more about Hydrogen bonding refer here:

https://brainly.com/question/30885458#

#SPJ11

Answer:

chemical formula

Explanation:

Once chewed and swallowed, the food will be digested and absorbed nutrients, while the rest of the food will be excreted through the body's feces. This digestion process can take about 24-72 hours.

The process of digestion of food in humans can be divided into two types, namely mechanical digestion and chemical (enzymatic) digestion. Mechanical digestion is the process of changing food from a large or coarse form to a smaller or finer form. The process takes place in the mouth with the help of teeth and tongue. The mechanical digestion process also occurs in the stomach with the help of peristaltic motion of the stomach wall, so that food is like being stirred. While the chemical digestion process is the process of converting food substances from complex forms into simpler forms with the help of digestive enzymes.

#SPJ4

Answer:

Pulse rate depends on the activity we do, while exercising theres need of more oxygen so it increases but while at rest body requires less oxygen so low pulse rate.

When writing a sentence that begins with a numerical value, the correct number style to use depends on the specific style guide being followed. Generally, it is best to spell out the number in words at the beginning of a sentence, especially for numbers that are less than 10.

This is because it makes the sentence easier to read and avoids confusion with other symbols or punctuation marks.

In the case of the given sentence, "Three-fourths of the respondents" is the correct choice for the number style at the beginning of the sentence. This is because the number is less than 10 and it is expressed in words, which is the preferred style for starting a sentence.

Additionally, it is important to be consistent in the use of number styles throughout a document or piece of writing. If a particular style guide is being followed, it is best to adhere to its recommendations for consistency and clarity.

Overall, when writing a sentence that begins with a numerical value, it is important to consider the specific style guide being followed and to choose a number style that is clear and consistent throughout the writing.

Learn more about beginning here:

https://brainly.com/question/31381854

#SPJ11

Answer:

0.85 Molar Na2O

Explanation:

Determine the moles of sodium oxide, Na2O, in 10 grams by dividing by the molar mass of Na2O (61.98 g/mole).

 (10 g Na2O)/(61.98 g/mole) = 0.161 moles Na2O.

Molar is a measure of concentration.  It is defined as moles/liter.  A 1 M  solution contains 1 mole of solute per liter of solvent.  [200 ml water = 0.2 Liters water.]

In this case, we have 0.161 moles Na2O in 0.200 L of solvent.

 (0.161 moles Na2O)/(0.200 L) = 0.85 Molar Na2O

Answer:

How can gas become a liquard

Explanation:

air filter

Answer:

1.VOLUME– The amount of space an object takes up. Basic Unit (SI Unit) for Solids – Cubic Meter, m3. LENGTH/DISTANCE – The measurement between two points.

2.one particle per cubic meter.

3.it means it is heavier

4.In a liquid the particles are still close together but a little further apart than in a solid.

5.In gases the particles are much further apart than in solids or liquids.

Explanation:

thats all i can type lol

Answer:

0.1 im pretty sure

because

All those squares equal to 1

So if we use some good ole division

We get 0.1

Certain e-cigarette devices with high-power settings and sub-ohm coils can emit higher levels of metals, such as nickel and silver, compared to regular cigarettes.

There is evidence to suggest that certain types of electronic cigarettes (e-cigarettes) can emit higher levels of metals, including nickel and silver, compared to regular cigarettes.

However, it's important to note that the specific metal emissions can vary depending on various factors, such as the design, construction, and use of the e-cigarette device.Research studies have found that e-cigarette aerosols can contain metals such as nickel, silver, lead, chromium, and cadmium, among others.

The levels of these metals can vary significantly between different e-cigarette brands, models, and even individual devices. Some studies have reported higher levels of certain metals in e-cigarette aerosols compared to regular cigarette smoke, while others have found similar or lower levels.

It's worth mentioning that the presence of metals in e-cigarette aerosols can be attributed to several factors, including the heating element used in the device, the composition of the e-liquid, and the temperature at which the device operates.

Certain types of e-cigarette coils or atomizers, particularly those made from low-grade materials or with poor construction, may lead to increased metal emissions.To minimize potential exposure to metals, it is advisable to choose e-cigarette devices from reputable manufacturers and to avoid using low-quality or counterfeit products.

Additionally, following proper maintenance and cleaning procedures for e-cigarette devices can help reduce the risk of metal contamination.

It is important to note that while e-cigarette aerosols may contain higher levels of certain metals compared to regular cigarettes, the overall health risks associated with e-cigarette use are still being studied.

E-cigarettes are generally considered to be less harmful than traditional cigarettes, but they are not without risks, especially for non-smokers and young people. It is always recommended to exercise caution and make informed decisions regarding any form of nicotine or tobacco product use.

Learn more about electronic cigarettes

brainly.com/question/31955942

#SPJ11

Answer:

The answer is b.

Explanation:

Amorphous solids have two characteristic properties. When cleaved or broken, they produce fragments with irregular, often curved surfaces; and they have poorly defined patterns when exposed to x-rays because their components are not arranged in a regular array. An amorphous, translucent solid is called a glass.

Hope this helps list as brainlest

Answer:

15.5g

Explanation:

your welcome

Answer:

the third one

Explanation:

Answer:

a

Explanation:

Answer:

37.1g of Ca

Explanation:

Hello,

Molecular formula for calcium chloride = CaCl

Molar mass = 40 + 35.5 = 75.5g/mol

Assuming there's one mole of CaCl

1 mole = mass / molar mass

Mass = 1 × 75.5

Mass = 75.5g

75.5g of CaCl contains 40g of Calcium

70g of CaCl will contain x g of Calcium

X = (70 × 40) / 75.5

X = 37.086g

Therefore, 70g of CaCl contains approximately 37.1g of Ca

To answer your question, the useful buffering range of phosphoric acid and its conjugate base is approximately between pH 6.21 to 8.21.

This is because the pKa of phosphoric acid is 7.21, which means that at pH values below 6.21, most of the acid will be in its protonated form (H3PO4) and at pH values above 8.21, most of it will be in its deprotonated form (H2PO4-). However, within this buffering range, there will be a relatively equal distribution of both the protonated and deprotonated forms,

which allows for the acid-base pair to act as an effective buffer. The buffer capacity is the highest at pH = pKa and decreases as the pH moves away from pKa. The conjugate base of phosphoric acid is H2PO4-, and it acts as the base in the buffer system. In summary, the useful buffering range of phosphoric acid and its conjugate base is between pH 6.21 to 8.21, which allows for the acid-base pair to act as an effective buffer.

To know more about phosphoric acid visit:

https://brainly.com/question/30489231

#SPJ11

When steel and zinc were connected, zinc is the cathode. The term cathode refers to the electrode that is reduced during an electrochemical reaction.

The electrons are moved from the anode to the cathode during an electrochemical reaction in order to maintain a current in the wire that links the two electrodes.

According to the galvanic series, zinc is more active than iron, meaning that it is more likely to lose electrons and be oxidized. As a result, when steel and zinc are connected, zinc will act as the anode and lose electrons, whereas iron (steel) will act as the cathode and receive the electrons transferred by zinc.

To know more about electrochemical reaction visit:-

https://brainly.com/question/13062424

#SPJ11