Please help me, I don't bite. 3.

Answer:

Decomposition

Explanation:

If we look at the process;

2 NaHCO3 (s) → Na2CO3 (s) + H2O (g) + CO2 (g)

We can see that NaHCO3 was broken down into Na2CO3, H2O and CO2.

The breakdown of one compound to yield other chemical compounds is known as decomposition.

Hence the NaHCO3 was decomposed in the process above.

Answer: The first law of thermodynamics is a statement of conservation of energy.

Explanation:

According to the first law of thermodynamics, heat provided to a system is actually the sum of internal energy and work done by the system or on the system.

Mathematically, [tex]\Delta Q = \Delta U + \Delta W[/tex]

The first law of thermodynamics also means that energy can neither be created nor it can be destroyed. Hence, energy is conserved.

Thus, we can conclude that the first law of thermodynamics is a statement of conservation of energy.

Explanation:

is responsible for interrupting the interaction between pectins and solvent molecules

Answer:

When SO

2

is passed through an acidified solution of H

2

S, sulphur is precipitated out according to the reaction.

2H

2

S+SO

2

→2H

2

O+3S

Answer:

shduxhheufufffhduduf

Answer:

NH3 Ammonia

Explanation:

Ammonia has 4 regions of electron density around the central nitrogen atom (3 bonds and one lone pair). These are arranged in a tetrahedral shape. The resulting molecular shape is trigonal pyramidal with H-N-H angles of 106.7°.

Answer:

8 oxygen. 9 flourine. 10. Neon. 5 Boron

Answer:

it might reach to 4g per L

Answer:

The correct answer is - 0.0188 mJ*s^-1.

Explanation:

In order to convert the kPA value to PA value--

and then convert PA unit to 1 kgm^-1s^-2

And in finally convert mm to m

The value that come should be convert from kgm^2s^-2 to and then convert J to mJ or kJ by dividing 100 or 100 subsequently.

As no question given this method can be followed for the answer.

answer

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Answer:

NH4Cl > Li2SO4 > CoCl3

Explanation:

Let us recall that the freezing point depression depends on the molality of the solution and the number of particles present.

Let us also recall that freezing point depression is a colligative property. It depends on the number of particles present in solution.

Usually, the more the number of particles present, the lower the freezing point. Hence, NH4Cl which has only two particles will have the highest freezing point while CoCl3 which has four particles will have the lowest freezing point.

Answer:be careful and relax

Explanation:

Answer:

Hahaha be careful and relax

Answer:

3.88 atm

Explanation:

We'll begin by calculating the number of mole of CO₂ in each case. This can be obtained as follow:

For 2.50 g of CO₂:

Mass of CO₂ = 2.5 g

Molar mass of CO₂ = 12 + (2×16) = 44 g/mol

Mole of CO₂ =?

Mole = mass / molar mass

Mole of CO₂ = 2.5 / 44

Mole of CO₂ = 0.06 mole

For 0.42 g of CO₂:

Mass of CO₂ = 2.5 g

Molar mass of CO₂ = 44 g/mol

Mole of CO₂ =?

Mole = mass / molar mass

Mole of CO₂ = 0.42 / 44

Mole of CO₂ = 0.010 mole

Finally, we shall determine the new pressure. This can be obtained as follow:

Initial mole (n₁) = 0.06 mole

Initial pressure (P₁) = 4.65 atm

Final mole (n₂) = 0.06 – 0.010 = 0.05 mole

Final pressure (P₂) =?

NOTE: Temperature and volume is constant.

P₁ / n₁ = P₂ / n₂

4.65 / 0.06 = P₂ / 0.05

Cross multiply

0.06 × P₂ = 4.65 × 0.05

0.06 × P₂ = 0.2325

Divide both side by 0.06

P₂ = 0.2325 / 0.06

P₂ = 3.88 atm

Thus, the new pressure is 3.88 atm.

Answer: Sugar is added to water and initially completely dissolves, but eventually solid sugar collects on the bottom of the container. Sugar and water are both partially miscible. This produces a dynamic equilibrium. Ethanol (a liquid) is added to water and only a single layer is observed no matter how much ethanol is added. Ethanol and water are miscible.

Explanation:

When a substance (solute) dissolves partially in a solvent then it is known as partially miscible in the solvent. In such cases, a small amount of solute remains at the bottom of solution.

If a solute dissolves completely in solvent like water such that only one layer is seen in the solution then it means that the solute is miscible in solvent.

Thus, we can conclude that sugar is added to water and initially completely dissolves, but eventually solid sugar collects on the bottom of the container. Sugar and water are both partially miscible. This produces a dynamic equilibrium. Ethanol (a liquid) is added to water and only a single layer is observed no matter how much ethanol is added. Ethanol and water are miscible.

Answer:

SN1 substitution reaction

Explanation:

cyclohexanol is a secondary alkanol. The mechanism of acid catalysed dehydration of cyclohexanol involves the protonation of the -OH group.

This is followed by loss of water which is a good leaving group. At this stage, a proton could be abstracted to yield cyclohexene by E1 mechanism or an SN1 substitution reaction may occur to yield Cyclohexyl chloride.

The both reactions are equally likely.

Explanation:

A compound containing only two elements is called a binary compound.

(a). The compound HCN contains a hydrogen ion and cyanide ion. Hence, the name of HCN is hydrogen cyanide.

An aqueous solution of hydrogen cyanide is known as hydrogen cyanide solution.

(b). The compound HF contains a hydrogen ion and a fluorine ion. The suffix -ide will be added to its name. So, the name of this compound is hydrogen fluoride.

An aqueous solution of HF is known as hydrogen fluoride.

(c). The compound [tex]H_{2}S[/tex] contains two hydrogen atoms and one sulfur atom. The suffix -ide will be added to its name. So, the name of this compound is hydrogen sulfide.

An aqueous solution of this compound is known as hydrogen sulfide solution.

Answer:

747.5 mL

Explanation:

Assuming ideal behaviour, we can solve this problem by using Boyle's law, which states that at constant temperature:

Where in this case:

We input the data given by the problem:

And solve for V₁:

Answer:

Ba(OH)₂ + 2 HBr ⇒ BaBr₂ + 2 H₂O

Explanation:

We have the products of a reaction and we have to predict the reactants. Since the products are binary salt and water, this must be a neutralization reaction. In neutralizations, acids react with bases. The acid that gives place to Br⁻ is HBr, while the base the gives place to Ba²⁺ is Ba(OH)₂. The balanced chemical equation is:

Ba(OH)₂ + 2 HBr ⇒ BaBr₂ + 2 H₂O

Answer:

The student completed the experiment correctly and there were no errors in the experiment.

Explanation:

When a pea size amount of K2CO3 is dropped into a solution of HCl, the following reaction occurs;

K2CO3(s) + 2HCl(aq) ----> 2KCl(aq) + CO2(g) + H2O(l)

The gas CO2 does not support burning hence, when the student performed a splint test and observed that the splint was extinguished when he placed the splint into the test tube of the gas.

Hence, the experiment was properly conducted and the student completed the experiment correctly and there were no errors in the experiment.

Answer:

B₂O₃

Explanation:

Step 1: Calculate the mass of oxygen in 150 mg of boron oxide

Of 150 mg of boron oxide, 46.6 mg belong to boron. The mass of oxygen is:

150 mg - 46.6 mg = 103.4 mg

Step 2: Calculate the percent by mass of each element

We will use the following expression.

%Element = mElement/mCompound × 100%

%B = 46.6 mg/150 mg × 100% = 31.1%

%O = 103.4 mg/150 mg × 100% = 68.9%

Step 3: Divide each percentage by the atomic mass of the element

B: 31.1/10.81 = 2.88

O: 68.9/16.00 = 4.31

Step 4: Divide both numbers by the smallest one (2.88)

B: 2.88/2.88 = 1

O: 4.31/2.88 ≈ 1.5

Step 5: Multiply both numbers by 2 so that they are integers

B: 1 × 2 = 2

O: 1.5 × 2 = 3

The empirical formula is B₂O₃.

Answer:

2.29 M

Explanation:

Equation of the reaction;

Ca(OH)2(aq) + 2HClO4(aq) → 2H2O(l) + Ca(ClO4)2(aq)

Concentration of acid CA = 1.49 M

Concentration of base CB= ????

Volume of acid VA= 43.0 ml

Volume of base VB= 14.0 ml

Number of moles of acid NA = 2 moles

Number of moles of base NB = 1 mole

CAVA/CBVB = NA/NB

CAVANB =CBVBNA

CB= CAVANB/VBNA

CB= 1.49 × 43.0 × 1/14.0 × 2

CB= 2.29 M

Answer:

False

Explanation:

An object with a density less than the density of water will float.

And an object that is denser than water (more than 1.00g/mL) will sink when placed in water.

Answer:

1.02 Hz

Explanation:

frequency= (1/t) = (1/0.98) = 1.02 hz

Answer:

218.7 mL

Explanation:

The reaction that takes place is:

First we calculate how many HCOOH moles reacted, using the given volume and concentration:

As 1 HCOOH mol reacts with 1 LiOH mol, 32.8 mmoles of LiOH are needed to react with 32.8 mmoles of HCOOH.

Finally we calculate how many mL of a 0.150 M solution would contain 32.8 mmoles:

Answer:

It would take 200,000 years for a spaceship traveling at the speed of light to go across the entire galaxy.

Answer:

O B. Alkaline earth metals

Explanation:

Noble gases → 8th column.

Alkali metal → first column.

Halogen → 7th

Answer:

B. Alkaline earth metals

Explanation:

Alkaline-earth metals: The alkaline-earth metals make up Group 2 of the periodic table, from beryllium (Be) through radium (Ra). Each of these elements has two electrons in its outermost energy level, which makes the alkaline earths reactive enough that they're rarely found alone in nature. But they're not as reactive as the alkali metals. Their chemical reactions typically occur more slowly and produce less heat compared to the alkali metals.