only 2.6% of all water on earth is ___

I NEED HELPPP

the area of one of the cat's paws is 4 square centimeters.

The weight of the cat is 4.0 kilograms, which is the force exerted on the scale by the cat's body. The weight per unit area on the scale due to the cat's paws is 0.25 kilograms per square centimeter.

Let A be the area of one of the cat's paws in square centimeters. The weight of the cat is supported by all four paws, so the total force exerted by the paws on the scale is:

force = weight = 4.0 kg

The force exerted by one paw is one-fourth of the total force:

force per paw = force / 4 = 4.0 kg / 4 = 1.0 kg

This force is distributed over the area of one paw, so we can write:

pressure = force per paw / A

where pressure is the weight per unit area, which is given as 0.25 kg/cm

Substituting the values and solving for A, we get:

0.25 kg/cm = 1.0 kg / A

A = 1.0 kg / 0.25 kg/cm = 4 cm

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The balanced equation for the reaction would be 2AlPO4 + 3CuCrO4 → Al2(CrO4)3 + 3Cu3(PO4)2.

The formulas of the reactants are:

The formulas of the products are:

The balanced equation indicates that 2 moles of Aluminum Phosphite react with 3 moles of Copper (II) Chromate to produce 1 mole of Aluminum Chromate and 3 moles of Copper (II) Phosphate.

Thus: 2AlPO4 + 3CuCrO4 → Al2(CrO4)3 + 3Cu3(PO4)2

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The grams of water needed to create a 4 molal solution with 9 moles of NaOH is 2250 grams.

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T = 23 C + 273 = 296 K V(H2) = (1.7 mol*62360 mmHg/mol*K*296 /850 mmHg) = 36917.1 ml = 36.9 L if volume, per liters, of H2 gas is created at 26 C and 800 mmHg.

For instance, hydrogen is not harmful. Also, as hydrogen is that much lighter than the atmosphere, it evaporates quickly when it is discharged, enabling the fuel to disperse relatively quickly in the event of a leak. To ensure its safe use, some of hydrogen's features necessitate additional technical restrictions.

When two atoms of hydrogen join forces to form a hydrogen molecule, the result is a gas known as H2. Molecular hydrogen is another name for H2. There are two protons & two electrons in it. Hence, it has a neutral charge and is stable, making it the most prevalent type of hydrogen.

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Answer:

Hence, C121H199O100 represents the compound's empirical formula.

Explanation:

We must ascertain the ratio of the number of atoms of each element in the compound in order to derive the empirical formula. To accomplish this, we can divide the mole ratio by the least number of moles after converting the masses of each element to moles.

The elements' molar masses are as follows:

12.01 g/mol for carbon

1.01 g/mol for hydrogen

16.00 g/mol for oxygen

When we convert the masses to moles, we obtain:

48.38 g / 12.01 g/mol = 4.03 mol of carbon

6.74 g / 1.01 g/mol of hydrogen equals 6.67 mol

53.5 g / 16.00 g/mol = 3.34 mol for oxygen

3.34 mol of oxygen is the least amount of moles. If you divide the total moles of each element by 3.34 mol, you get:

Carbon: 4.03 mol/3.3 mol = 1.21 mol Hydrogen:6.67 moles/3.34 moles equals 1.99

3.34 mol / 3.34 mol = 1.00 for oxygen.

By multiplying each ratio by 100 to obtain whole integers, we may simplify the ratios, which are around 1.21:1.99:1.00. This results in a ratio of roughly 121:199:100.

We divide each number in the ratio by their greatest common factor (GCF) to arrive at the empirical formula. 121, 199, and 100 have a GCF of 1. By dividing by 1, we get:

Carbohydrate: 121 / 1 = 121

199 / 1 = 199 for hydrogen.

100 / 1 Equals 100 for oxygen.

Hence, C121H199O100 represents the compound's empirical formula.

Answer:

First, I will convert from grams to moles. This will give me approximately 4.032 moles of carbon, 6.740 moles of hydrogen, and 3.344 moles of oxygen. Then, I will calculate the mole ratio, using whole numbers. I must also identify the least amount of moles in an element for this step, which is oxygen at 3.344 moles.

Oxygen = 3.344/3.344 = 1

Carbon = 4.032/3.344 = 1

Hydrogen = 6.740/3.344 = 2

The empirical formula will be COH2.

Now that we have the molar mass of the molecular formula, we can calculate for the molecular formula. First, we will begin by discovering the molar mass of the empirical formula, which will be C molar mass x 1 + O molar mass x 1 + H molar mass x 2. That will be equal to 60.949. After that, we can divide the molecular mass by the empirical formula molar mass, giving us approximately 3. Now we will multiply the empirical formula by 3, giving us our molecular formula, which will be equal to C3O3H6.

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The new pressure of the gas with a solubility of 24 g/L will be222 kPa.

The solubility of the gas in the liquid is directly proportional to the partial pressure of a gas above the liquid. This relationship is described by Henry's Law, which states that the solubility of a gas is proportional to its partial pressure:

C = kP

where C is the concentration of the gas in the liquid (in units of g/L), P is the partial pressure of the gas above the liquid (in units of kPa), and k is the proportionality constant.

If we know the solubility of the gas at one pressure, we can use Henry's Law to calculate the solubility at a different pressure. For example, if the solubility of the gas is 48 g/L at 444 kPa, and we want to know the solubility at a new pressure, we can use the following formula:

P₁ / P₂ = C₁ / C₂

where P₁ is the initial pressure, P₂ is the new pressure, C₁ is the initial concentration (solubility) at P₁, and C₂ is the new concentration (solubility) at P₂.

Rearranging this formula, we get:

C₂ = C₁ x (P₂ / P₁)

Substituting the given values, we have:

C₁ = 48 g/L (solubility at 444 kPa)

P₁ = 444 kPa

C₂ = 24 g/L (desired solubility at new pressure)

P₂ = ?

Solving for P₂, we get:

P₂ = (C₂ x P₁) / C₁

P₂ = (24 g/L x 444 kPa) / 48 g/L

P₂ = 222 kPa

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There are approximately 6.031 x 10^23 molecules of O2 gas contained in 1357 mL of O2 gas at −14°C and 1437 torr.

we can use the ideal gas law:

PV = nRT

where, P = pressure of the gas in torr,

V = volume of the gas in liters,

n = number of moles of gas,

R = ideal gas constant (0.08206 L·atm/mol·K),

T = temperature of the gas in Kelvin.

the volume of the gas from milliliters (mL) to liters (L):

V = 1357 mL / 1000 mL/L

V = 1.357 L

Now to convert the temperature of the gas from Celsius (°C) to Kelvin (K):

T = -14°C + 273.15

T = 259.15 K

Substituting the given values:

(1437 torr) (1.357 L) = n (0.08206 L·atm/mol·K) (259.15 K)

n = (1437 torr x 1.357 L) / (0.08206 L·atm/mol·K x 259.15 K)

n = 1.0008 mol

the number of moles of O2 gas contained in 1357 mL of O2 gas at −14°C and 1437 torr is 1.0008 mol. To find the number of molecules,

we can use Avogadro's number:

1 mol of O2 gas contains 6.022 x 10^23 molecules

So, the number of molecules in 1.0008 mol of O2 gas is:

(1.0008 mol) x (6.022 x 10^23 molecules/mol) = 6.031 x 10^23 molecules

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It stays much colder than traditional ice packs with the added bonus of no condesation building up on the inside of the travel box, like no water to make everything soggy &wet? However never take a huge breath of the contents as you open the box or container because inhaling trapped dry ice gas can be very harmful to your lungs! Simply let it mix with the air then carefully use gloves to move any dry ice away from your product and it should still be very frozen. We do this for long distance wedding cake delivery and I've never had one melt, 2 hours or more of driving to the events! Hope this helps!

Therefore, 0.00723 moles of Na3C6H5O7 can be produced if one tablet containing 0.0217 mol of NaHCO3 is dissolved.

The balanced chemical equation shows that 3 moles of NaHCO3 react with 1 mole of H2C6H6O7 to produce 1 mole of Na3C6H5O7. Therefore, the number of moles of Na3C6H5O7 produced is directly proportional to the number of moles of NaHCO3.

If one tablet containing 0.0217 mol of NaHCO3 is dissolved, then according to the balanced chemical equation, the number of moles of Na3C6H5O7 produced is:

(0.0217 mol NaHCO3) x (1 mol Na3C6H5O7 / 3 mol NaHCO3) = 0.00723 mol Na3C6H5O7

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Answer:

burn

Explanation:

we burn fossil fuels, which releases carbon into the atmosphere

Answer:

polution

Explanation:

if the global of earth all polution in earth so,use electric bike

The various types of chemical reaction are Combination Reaction,Decomposition Reaction,Displacement Reaction,Double Displacement Reaction, and Precipitation Reaction.

A chemical reaction is defined as the reaction that involves the combination of two or more substances leading to the formation of a new substance called the product of the reaction.

The various types of chemical reaction include the following:

There are three parts of a chemical reaction which is the reactant part, the arrow and the product part.

That is;

A. + B ---------> D + E.

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If 9.7 mol of CO₂ are produced, 14.55 moles of O₂ were reacted.

In chemistry, a mole is a unit of measurement that represents an amount of substance. This number of entities is known as Avogadro's number, which is approximately equal to 6.02 x 10^23.

The mole is a convenient unit for measuring the amount of substance in chemical reactions, because it allows chemists to predict and calculate the quantities of reactants and products involved in a chemical reaction. For example, if we know the balanced chemical equation for a reaction, we can use the stoichiometry of the reaction to determine the amount of reactants needed to produce a given amount of product, or the amount of product that can be produced from a given amount of reactants.

The balanced chemical equation for the combustion of ethylene (C2H4) in oxygen is:

C₂H₄ + 3O₂ → 2CO₂ + 2H₂O

From the balanced equation, we can see that 3 moles of O₂ react with 1 mole of C₂H₄ to produce 2 moles of CO₂. Therefore, the number of moles of O₂ that reacted can be calculated as:

moles of O₂ = (moles of CO₂ produced) × (3/2)

moles of O₂ = 9.7 mol × (3/2)

moles of O₂ = 14.55 mol

Therefore, 14.55 moles of O₂ were reacted.

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Answer:

Answer :

The compounds are separated by using a suitable filtration technique.

Explanation:

Explanation:

The compounds are separated by using a suitable filtration technique. NaCl remains in the filtrate, but charcoal remains on the filter paper. Crystals of NaCl can be obtained by the method of evaporation.

The synthesis of carboxylic acid can be done by hydrolysing the nitrile which is substituted in place of halide by using cyanide ion. The structure that contains a nitrile is OCH2C≡N.

A nitrile is an organic compound that contains a carbon triple bonded to a nitrogen atom.

The general formula for a nitrile is R–C≡N, where R is an alkyl or aryl group. In the structure OCH2C≡N, the OCH2 group is the alkyl group and the C≡N is the nitrile functional group. Therefore, this structure contains a nitrile.

To synthesize a carboxylic acid from an alkyl halide, you can first convert the alkyl halide to a nitrile through a substitution reaction with a cyanide ion. The nitrile can then be hydrolyzed to form a carboxylic acid. The overall reaction is:

R–X + CN– → R–C≡N → R–COOH

Where R is an alkyl or aryl group, X is a halogen, and CN– is a cyanide ion.

In conclusion, the structure that contains a nitrile is OCH2C≡N and it can be used to synthesize a carboxylic acid from an alkyl halide through a substitution reaction followed by hydrolysis.

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This means that for every liter of water, there is 6.15 moles of the substance dissolved in it.

Substance is a concept that refers to a physical material or thing that has mass and occupies space. It is a fundamental concept of physics that applies to all physical and visible things in the universe. In philosophy, substance is a primary category of ontology that refers to the physical or material existence of things.

The molarity of the saturated solution can be calculated by dividing the solubility (360 g/L) by the molar mass of the substance (58.5 g/mol).
The molarity of the saturated solution is thus 6.15 mol/L.
This means that for every liter of water, there is 6.15 moles of the substance dissolved in it.

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Answer: First, we need to calculate the total fuel consumption per day for all 380 SSTs:

Fuel consumption per hour: 5,320 gallons

Number of planes: 380

Hours per day: 14

Total fuel consumption per day = 5,320 x 380 x 14 = 28,190,400 gallons

Next, we need to convert gallons to metric tons of jet fuel:

1 gallon = 0.00378541 metric tons

28,190,400 gallons = 106,698.89 metric tons

Now, we can calculate the total crude oil needed to produce this amount of jet fuel:

1 ton of jet fuel = 7,000 kilograms of crude oil

106,698.89 tons of jet fuel = 746,892,230 kilograms of crude oil

To convert kilograms to metric tons:

1 metric ton = 1,000 kilograms

746,892,230 kilograms = 746,892.23 metric tons

Finally, we can calculate the percentage of crude oil production used for SST fuel:

World crude oil production in 1990 = 4.02 x 10^9 metric tons

Percentage of crude oil used for SST fuel = (746,892.23 / 4.02 x 10^9) x 100

= 0.0186%

Therefore, approximately 0.0186% of the crude oil production in 1990 was used for fuel for the SSTs.

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Answer:

10. methanol would be more.

11. methanol would be more.

12. methanol would remain the same.

13. CO would be less.

Explanation:

10. Methanol increases because the forward reaction is favoured with increase in temperature and thus it is endothermic.

11. Methanol increases because the forward reaction is favoured with decrease in volume thus increasing pressure decreases the volume of the vessel.

12.Methanol remains the same because the hydrogen added is its raw material but the CO is acting as a limiting reactant for the formation of methanol.

13. Carbon monoxide becomes less because it will rapidly combine with hydrogen added to form methanol and then later be a limiting reactant when hydrogen is still present

The percentage by mass of water in the hydrate [tex]CuSO^{4}.5H^{2}O[/tex] is 47.6%.

The percentage composition of each of the following compounds are

1.a. NaClO:

The molar mass of NaClO =

22.99 g/mol + 35.45 g/mol + 15.99 g/mol = 74.43 g/mol

Percentage composition of Na =

(22.99 g/mol / 74.43 g/mol) *  100 \ percent \ = 30.9percent

Percentage composition of Cl =

(35.45 g/mol / 74.43 g/mol) *  100percent \ =  47.6percent

Percentage composition of O =

(15.99 g/mol / 74.43 g/mol) * 100percent \ =  21.5percent

Therefore, the percentage composition of NaClO is approximately:

30.9% Na, 47.6% Cl, and 21.5% O.

1.b. [tex]Al^{2}(SO^{3})^{3}[/tex]:

The molar mass of [tex]Al^{2}(SO^{3})^{3}[/tex] = [tex]2 * (26.98 g/mol) + 3 * (32.06 g/mol + 3 * 16.00 g/mol) = 342.14 g/mol[/tex]

Percentage composition of Al =

[tex](2 * 26.98 g/mol / 342.14 g/mol) * 100 \ = 3.99[/tex]%

Percentage composition of S =

[tex](3 * 32.06 g/mol / 342.14 g/mol) * 100 \ = 8.99[/tex]%

Percentage composition of O =

[tex](9 * 16.00 g/mol / 342.14 g/mol) * 100 \ = 10.47[/tex]%

Therefore, the percentage composition of [tex]Al^{2}(SO^{3})^{3}[/tex] is approximately:

3.99% Al, 8.99% S, and 10.47% O.

1.c. [tex]C^{2}H^{5}COOH[/tex]:

The molar mass of [tex]C^{2}H^{5}COOH[/tex] = [tex]2 * (12.01 g/mol) + 6 * (1.01 g/mol) + 12.01 g/mol + 16.00 g/mol = 60.05 g/mol[/tex]

Percentage composition of C =

[tex](2 * 12.01 g/mol / 60.05 g/mol) * 100 \ = 40.0[/tex]%

Percentage composition of H =

[tex](6 * 1.01 g/mol / 60.05 g/mol) * 100\ \ = 10.1[/tex]%

Percentage composition of O = [tex](2 * 16.00 g/mol + 12.01 g/mol / 60.05 g/mol) * 100 \ = 49.9[/tex]%

Therefore, the percentage composition of [tex]C^{2}H^{5}COOH[/tex] is approximately:

40.0% C, 10.1% H, and 49.9% O.

1.d. [tex]BeCl^2[/tex]:
The molar mass of [tex]BeCl^2[/tex] = [tex]9.01 g/mol + 2 * 35.45 g/mol = 79.91 g/mol[/tex]

Percentage composition of Be = [tex](9.01 g/mol / 79.91 g/mol) * 100 \ = 11.3[/tex]%

Percentage composition of Cl =

[tex](2 * 35.45 g/mol / 79.91 g/mol)* 100 \ = 88.7[/tex]%

Therefore, the percentage composition of [tex]BeCl^2[/tex] is approximately:

11.3% Be and 88.7% Cl.

2. [tex]CuSO^{4}.5H^{2}O[/tex]:

Mass of CuSO4.5H2O = 8.40 g

Mass of anhydrous [tex]CuSO^{4}[/tex] = mass of [tex]CuSO^{4}.5H^{2}O[/tex] - mass of water

Mass of water = mass of [tex]CuSO^{4}.5H^{2}O[/tex] - mass of anhydrous CuSO4

[tex]= 8.40 g - 4.40 g= 4.00 g[/tex]

So, the mass of water in the hydrate is 4.00 g.

To determine the percentage by mass of water in the hydrate, we need to divide the mass of water by the mass of the entire compound ([tex]CuSO^{4}.5H^{2}O[/tex]) and multiply by 100%:

Percentage by mass of water = (mass of water/mass of [tex]CuSO^{4}.5H^{2}O[/tex]) x 100%

[tex]= (4.00 g/8.40 g) * 100= 47.6[/tex]%

Therefore, the percentage by mass of water in the hydrate [tex]CuSO^{4}.5H^{2}O[/tex] is 47.6%.

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Answer: In the chlor alkali process, sodium hydroxide is prepared from common salt (sodium chloride). The byproducts are hydrogen gas and chlorine gas. Electrolysis of aqueous sodium chloride (brine solution) in Castner-kellner cell gives sodium hydroxide, chlorine gas and hydrogen gas.

Answer: Useful substances are obtained from common salt by the process of electrolysis

The pH of the 0.30 M solution of sodium formate is 2.13.
The correct answer is E. 2.13.

Formic acid dissociates in water to form hydrogen formate (HCOO-) and a proton (H+).

Since the Ka of HCOOH is [tex]1.8 * 10^{-4}[/tex], the Kb of HCOO- is equal to Ka x Kb = ([tex]1.8 * 10^{-4}[/tex])([tex]1.0 * 10^{-14}[/tex]) = [tex]1.8 * 10^{-18}[/tex].

The ionization of sodium formate (NaHCOO) can be represented as:

[tex]NaHCOO + H^2O < = > HCOO^- + Na^+ +[/tex] [tex]H^3O^+[/tex]

We can use the Kb of HCOO- to calculate the equilibrium concentrations of the species in the solution.

[HCOO-] = [NaHCOO] = 0.30 M

[Na+] = [[tex]H^3O^+[/tex]] = 0

Kb = [HCOO-][[tex]H^3O^+[/tex]]/[NaHCOO]

1.8 x 10-18 = (0.30)(x)/(0.30)

x = 1.8 x 10-18

The pH of the solution can then be calculated using the equation:

pH = -log[[tex]H^3O^+[/tex]]

pH = -log(1.8 x 10-18)

pH = 2.13

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Question should be like

Calculate the pH of a 0. 30 M solution of sodium formate (NaHCOO) given that the Ka of formic acid (HCOOH) is 1. 8 x 10^-4.

A. 8. 61

B. 10. 26

C. 11. 87

D. 5. 39

E. 2. 13

All the statements are about the acidity of compounds, of which statement 1, 3 & 4 are true and statement 2 is false.

Statement 1: "the strength of an acid depends primarily on the conjugate base's ability to support a negative charge" is true because, a strong acid has a weak conjugate base, which means it is less able to support a negative charge.

Statement 2: "induction is long range electronegativity, and the presence of electronegative atoms improves acidity of distant H" is false.

Because, induction is the ability of an electronegative atom or group to withdraw electron density from a neighbouring atom or group, leading to an increase in acidity.

However, this effect is not long range, and typically only affects neighbouring atoms.

Statement 3: "H bonded to larger atoms are more acidic due to poor orbital overlap, and polarizability of large orbitals" is true.

Because larger atoms have larger orbitals, which leads to poor orbital overlap and weaker bonds with hydrogen.

This makes it easier for the hydrogen to dissociate and increases the acidity of the compound.

Statement 4: "increasing the % of s-orbital character in a bond increases acidity" is true.

S-orbitals are closer to the nucleus and have a lower energy than p-orbitals, leading to stronger bonds and increased acidity.

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The red-colored blocks indicate non metals in the periodic table. Nonmetals are located on the right side of the periodic table, in the p-block.

Non-metals are composed of a variety of elements, such as carbon, nitrogen, oxygen, sulfur, phosphorus, and selenium. These elements are generally non-reactive, but some of them can form compounds with other elements. They are also used in various industries, such as the production of plastics, fertilizers, and explosives. Non-metals are divided into two categories: metalloids and non-metalloids. Nonmetals are characterized by their lack of luster and their low thermal conductivity.

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North America is experiencing spring during the position when the Northern Hemisphere is tilted towards the Sun, which occurs around March 20th to 21st, known as the Vernal Equinox.

The point in the Earth's orbit around the Sun when the tilt of axis is neither towards nor away from the Sun is known as the Vernal Equinox, also known as the Spring Equinox. Because of this arrangement, the length of day and night is almost identical over the whole globe. This occasion, which occurs in North America around March 20–21, heralds the start of the spring season. The Northern Hemisphere begins to tilt towards the Sun around this time, lengthening the day and raising temperatures. Agriculture, migratory patterns, and different cultural holidays are significantly impacted by this change in the Earth's position.

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Answer:

6 moles of H2O

Explanation:

We need the balanced equation for this reaction.

   C2H2 + O2 = CO2 + H2O

   2C2H2 + 5O2 = 2CO2 + 4H2O   [Balanced reaction]

The balanced reaction tells us that we should expect to obtain 4 moles of water, H2), for every 2 moles of C2H2 (ethylene).

That is a ratio:  (4 moles H2O)/(2 moles C2H2) or (2/1)(moles H2O/moles C2H4)

If we start with 3 moles of C2H4:

 (3 moles C2H4)*((2 moles H2O)/(1 moles C2H2)) = (2*3/1) moles H2O [the moles C2H2 cancel]

(2*3/1) moles H2O = 6 moles of H2O

The process that could result in the net movement of a substance into a cell, if the substance is more concentrated in the cell than in the surroundings is called osmosis.

Osmosis is a passive transport process where water molecules move from an area of high concentration to an area of low concentration through a selectively permeable membrane. In this process, a solute moves from a region of high concentration to a region of low concentration. A selectively permeable membrane is a type of biological membrane that allows certain molecules or ions to pass through it by diffusion and occasionally specialized "facilitated diffusion" and passive or active transport processes, while preventing other molecules or ions from passing through it. Therefore, the correct answer is the option C - Osmosis.

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Answer:

We can begin by using the balanced chemical equation for the reaction between carbon monoxide and oxygen:

2CO + O2 -> 2CO2

This tells us that 2 volumes of CO react with 1 volume of O2 to produce 2 volumes of CO2. Since we have equal volumes of CO and O2, the limiting reactant will be the one that requires more volume, which is the CO:

2 volumes of CO + 1 volume of O2 -> 2 volumes of CO2

Using the ideal gas law, we can convert the volumes of CO and O2 at STP (standard temperature and pressure, which is 0°C and 1 atm) to moles:

n(CO) = V(CO) / Vm = 60 cm3 / 22.4 L/mol = 0.00268 mol

n(O2) = V(O2) / Vm = 30 cm3 / 22.4 L/mol = 0.00134 mol

Since 2 volumes of CO react with 1 volume of O2, we can say that the reaction will use up 2 x 0.00134 = 0.00268 mol of O2. Since we have 0.00134 mol of O2 initially, this means that all of the O2 will be used up in the reaction, leaving none in the residual gases. The reaction will also produce 2 x 0.00268 = 0.00536 mol of CO2.

Using the ideal gas law again, we can convert the volume of CO2 produced to a volume at STP:

V(CO2) = n(CO2) x Vm = 0.00536 mol x 22.4 L/mol = 0.120 cm3

Therefore, the volume of residual gases after the reaction is:

V(residual) = V(total) - V(CO) - V(O2) - V(CO2) = 90 cm3 - 60 cm3 - 30 cm3 - 0.120 cm3 = 0.880 cm3