What happens to the intensity of light emitted from stars the further away the star is from us?

Answer:

3132 is the answer

Explanation:

3BaCl2 + Al2S3 → 3BaS + 2AlCl3

Answer:

Explanation:

Hope this helps u !!

Answer:

The given molecules are:

(A) CO2 (B) H2O (C) CH4 (D) C2H4 (E) PH3

Which one has trigonal pyramidal geometry?

Explanation:

According to VSEPR (valence shell electron pair repulsion) theory, a molecule with a central atom having hybridization sp3 and with one lone pair of electrons has trigonal pyramidal geometry.

Among the given molecules,

CO2 has central atom carbon with sp hybridization without lone pairs.

So, it is a linear molecule.

H2O, the central atom is oxygen with sp3 hybridization and oxygen has two lone pairs. So, its geometry is V-shape or bent.

CH4 has central atom carbon with sp3 hybridization and no pairs.

So, its geometry is tetrahedral.

C2H4 ethene has carbon atoms as the central atoms with sp2 hybridization and carbon has no lone pairs.

So, its geometry is trigonal planar.

Answer:

PH3 has central atom P with sp3 hybridization.

P has one lone pair on it.

Hence, the geometry of PH3 is trigonal pyramidal.

Answer:

[He] 2s²

Explanation:

Answer:

double displacement reaction

Answer:

The empirical formula is: CH2

Th powder is not vainillin

Explanation:

We can find empirical formula of a compound CₐHₓOₙ knowing that moles CO2 = Moles C, 2 Moles H2O = Moles H and that we can find the mass of oxygen by the difference of masses of the atoms:

Moles C = Moles CO2 -Molar mass: 44.01g/mol-

5.875g * (1mol/44.01g) = 0.1335 moles C * (12.01g/mol) = 1.60gC

Moles H2O and moles H -Molar mass: 18.01g/mol-

2.41g H2O * (1mol / 18.01g) = 0.1339 moles H2O * (2mol H / 1mol H2O) =

0.2676 moles H * (1g/mol) = 0.27g H

The empirical formula of this compound is the ratio of C:H:

0.2676 moles H / 0.1335 moles C = 2

The empirical formula is:

CH2

In vainillin, the moles of Carbon = Moles of Hydrogen. the experiment shows the moles of hydrogen are twice the moles of carbon. Thus, the powder is not vainillin

Answer:

0.13 molL-1

Explanation:

We must first obtain the number of moles of sodium carbonate as follows;

Number of moles = mass/molar mass

Number of moles = 21.2 g/106 g/mol

Number of moles= 0.2 moles

Number of moles = concentration × volume

Volume = 1.50 L

Concentration = number of moles/volume

Concentration = 0.2 moles/1.5 L

Concentration = 0.13 molL-1

Answer:

B. Cation

Explanation:

As an electron is removed from the atom it is then converted into a positively charged ion known as a Cation.

Hope this helps u

Answer:

[tex]\boxed {\boxed {\sf 81.4 \ g\ KOH}}[/tex]

Explanation:

We are asked to convert 1.45 moles of potassium hydroxide (KOH)  to grams.

The molar mass is the mass in grams of 1 mole of a substance. The values are found on the Periodic Table. They are the same as the atomic masses but the units are grams per mole (g/mol) instead of atomic mass units (amu).

We have the compound KOH. Look up the molar masses of the individual elements.

The formula for the compound has no subscripts, so there is 1 mole of each element in 1 mole of the compound. We can simply add the molar masses.

Based on the molar mass, there are 56.105 grams of KOH in 1 mole. Create a ratio using this information.

[tex]\frac {56.105 \ g\ KOH}{ 1 \ mol \ KOH}[/tex]

We are converting 1.45 moles of KOH to grams, so we multiply by this value.

[tex]1.45 \ mol \ KOH *\frac {56.105 \ g\ KOH}{ 1 \ mol \ KOH}[/tex]

The units of moles of KOH cancel.

[tex]1.45\ *\frac {56.105 \ g\ KOH}{ 1 }[/tex]

[tex]81.35225 \ g\ KOH[/tex]

The original measurement of moles has 3 significant figures, so our answer must have the same.

For the number we calculated, that is the tenths place. The 5 in the hundredths place (81.35225) tells us to round the 3 up to a 4.

[tex]81.4 \ g\ KOH[/tex]

Approximately 81.4 grams of potassium hydroxide are represented by 1.45 moles.

Answer:

Tick

1

2

4

6

Explanation:

magnesium is not a good conductor has some free electrons but it is not used that much in the industries because of other better alternatives.

You can tick number 5 as wlee. Good luck

Answer:

the answer is a

Explanation:

it'sa silver-white an earth metal

Answer:

A. The reactants are changed to form the products.

Explanation:

Chemical reactions are reactions that involves a change in the chemical composition of substances involved while a nuclear reaction is the process of fusing together or splitting the nucleus of an atom. According to this question, matter is said to undergo both types of reaction.

However, one similarity in both chemical and nuclear reactions is that substances called REACTANTS are changed to form PRODUCTS. In nuclear reaction, the atoms joined or split are the reactants while the ones formed are the products.

Answer: A

Explanation:

Answer: The correct option is D) [tex]Ag^+[/tex]

Explanation:

The oxidation reaction is defined as the reaction in which a chemical species loses electrons in a chemical reaction. It occurs when oxidation number of a species increases.

A reduction reaction is defined as the reaction in which a chemical species gains electrons in a chemical reaction. It occurs when oxidation number of a species decreases.

For the given chemical reaction:

[tex]Zn^0+2Ag^+\rightarrow Zn^{2+}+2Ag^0[/tex]

On the reactant side:

Oxidation number of Zn = 0

Oxidation number of Ag = +1

On the product side:

Oxidation number of Zn = +2

Oxidation number of Ag = 0

As the oxidation number of Ag is decreasing from +1 to 0. Thus, [tex]Ag^+[/tex] is getting reduced.

Hence, the correct option is D) [tex]Ag^+[/tex]

Answer:

a. 408g de NH3 son necesarios

b. 2.42x10²³ moléculas de agua se obtienen

Explanation:

a. Basados en la reacción, 2 moles de NH3 producen una mol de (NH2)2CO. Para resolver esta pregunta debemos convertir la masa de (NH2)2CO a moles. Estas moles a moles de NH3 y su respectiva masa:

Moles (NH2)2CO -Masa molar: 60.06g/mol-

720g * (1mol / 60.06g) = 11.99 moles (NH2)2CO

Moles NH3:

11.99 moles (NH2)2CO * (2mol NH3 / 1mol (NH2)2CO) = 23.98 moles NH3

Masa NH3 -17.031g/mol-:

23.98 moles NH3 * (17.031g / mol) = 408g de NH3 son necesarios

b. 1mol de CO2 produce  1mol de agua. Se debe convertir el volumen a moles usando PV = nRT. Estas moles = Moles de agua. 1mol = 6.022x10²³ moléculas:

Asumiendo STP:

PV = nRT; PV / RT = n

Donde P = 1atm a STP

V = 9L

R = 0.082atmL/molK

T = 273.15K a STP

1atm*9L / 0.082atmL/molK*273.15K = n

n = 0.402 moles CO2 = Moles H2O

Moléculas:

0.402 moles agua * (6.022x10²³ moléculas / 1mol) =

Answer:

2.34 %

Explanation:

Since the density of the Jello, ρ = 1.14 g/mL and ρ = m/v where m = mass of jello and v = volume of jello = 475 mL.

So, m = ρv

substituting the values of the variables into the equation, we have

m = ρv

m = 1.14 g/mL × 475 mL = 541.5 g

Since we have 13 g of sugar in the jello, the total mass present is 13 g + 541.5 g = 554.5 g

So, the percentage by mass of sugar present % m/m = mass of sugar present/total mass × 100 %

= 13 g/554.5 g × 100 %

= 0.0234 × 100 %

= 2.34 %

So, the percentage by mass of sugar present % m/m = 2.34 %

Considering the definition of alkanes, single bonds are found in an alkane.

Alkanes are a class of hydrocarbons (compounds containing only carbon and hydrogen) that are made up of a variable number of carbon atoms joined together by single bonds. In turn, each carbon atom bonds to hydrogen atoms, which may eventually be replaced by other atoms or functional groups.

In other words, alkanes are open or closed chain molecules that are linked by simple bonds.

Alkanes are saturated hydrocarbons because the bonds between carbon atoms are simple and stable. And as mentioned, the hydrogen atoms bonded to each carbon atom can be replaced by other atoms, such as halogens (fluorine, bromine, chlorine) or various groups or “radicals”. In the latter case, the structure becomes more complex giving rise to branched alkanes.

In summary, single bonds are found in an alkane.

Learn more about alkanes:

brainly.com/question/1831557

brainly.com/question/27455385

brainly.com/question/4299529

#SPJ1

Answer: C) single only

Explanation:

just got it right

Answer:

ok

Explanation:

A salt is a neutral ionic compound. Let's see how a neutralization reaction produces both water and a salt, using as an example the reaction between solutions of hydrochloric acid and sodium hydroxide. The overall equation for this reaction is: NaOH + HCl -> H2O and NaCl.

Answer:

The answer is c

Answer:

125 ohms

Explanation:

since they're parallel we do

1/total resistance = (1/250 ohms) + (1/250 ohms)

then you get 2/250 ohms

then you flip it so it's equal to total resistance/1

250÷2= 125

Answer:

External stimulus of thirst

Answer:

your answer is:         the external stimulus of thirst

Explanation:

I took the test :)) hope this helps!!!!!!

Answer:

121 aprox.

Explanation:

mass/molar mass = Q/CF

where mass=?

molar mass of Al=27

Q=It = 15×24×60×60

C=3

F=96500

Answer:

STP is 101.325 kPa pressure and 273K temperature

Also, at STP, 1 mol of an ideal gas = 22.4 L

Since the question states that 22.4 L are needed at STP, we know that ONE MOLE is needed.  Now, the question is, how many moles are actually present?

V = 25.0 L

P = 101.5 kPa

T = 373K

n = ?

R = 8.31 L-kPa/Kmol

Solving the ideal gas law for n (moles) and comparing that to 1 mole, we have...

n = PV/RT = (101.5)(25.0)/(8.31)(373)

n = 0.82 moles of gas.  THIS IS NOT ENOUGH as it is less than the ONE mole required.

Explanation:

Answer:

hope it help u !!!!

Explanation:

Stoichiometry is the relationship between the relative quantities of substances taking part in a reaction or forming a compound, typically a ratio of whole integers

Explanation:

The haem is in turn split into iron , which forms chemical compounds as part of the blood iron pool available for future hemoglobin synthesis...

hope this help !!

It is thought that global dimming is probably due to the increased presence of aerosol particles in Earth's atmosphere, caused by pollution, dust, or volcanic eruptions. Aerosols and other particulates absorb solar energy and reflect sunlight back into space. ... Water droplets in clouds coalesce around the particles.

Global Dimming

source:

wikipedia via gooogle snippet