(Please help)
1.what is the most common isotope for element x

2.calculate the average atomic mass for element x

Answer:

An endothermic reaction is when heat is needed by the reaction, so it draws heat from its surroundings, making them feel cold. Just like a ice pack.

Answer:

atom is electrically neutral because

the no.of protons is equal to no.of

electrons.

Therefore the negative charge and

positive charge cancels out.

Explanation:

a unit of mass used to express atomic and molecular weights, equal to one twelfth of the mass of an atom of carbon-12.

Answer:

Atomic Mass Unit is also called Dalton. It is used to express atomic and molecular weight. It is defined as 1/12 of the mass of an unbound neutral atom of carbon.

Answer:

i think B is correct

Explanation:

Answer: C the “disappearance” of a small amount of mass.

Explanation:

Answer:

yes

Explanation:

because is smallest element that are made up of atom

Answer: Yes

Explanation:

Answer:

Radiometric dating or radioactive date is the method that uses radioisotope to date the formation of a rock. The age of the rocks will be determined.

Explanation:

Radioactive deterioration is a natural process and results from the unstable atomic core, which releases bits and parts.

These radioactive particles are released as (there are many types). This decline process results in a more equilibrated nucleus, which makes the atom stable when the number of protons and neutrons balances.

This radioactivity is suitable for dating, as a radioactive "parent" item is constantly decaying into a stable "daughter" element.

A single mineral grain or a whole rock may be dated. There are techniques by which the sample is excited in a nuclear reactor and then measured with a mass spectrometer. The isotope (such as in the argon-argon scheme).

Others put mineral grains under a special microscope, fir in the grains with an ionising laser beam that releases the mineral and the isotopes.

The isotopes are measured by a mass spectrometer inside the same machine (an example of this is SIMS analysis).

Answer:

the name of reaction that produces esters is dehydration.

Answer:

v2 = u2 + 2as

it is the correct answer

IF NOT THEN SORRY :)

Answer:

B. Lithium (Li) and iodine (1)

Explanation:

Ionic bond is a type of chemical bond that is formed between a metallic element and a non metallic element. The positive charge of the metallic ion is attracted to the negative charge of the non metallic ion to form an ionic bond.

According to the options given in this question, lithium and iodine will form an IONIC bond because lithium is a cation (+ve ion) while iodine is an anion (-ve).

Answer:

DD

Explanation:

Solution :

Cd(s) ---------------------->  [tex]Cd^{+2}[/tex] (aq) + 2[tex]e^-[/tex]      ,     [tex]E_0[/tex]  =   0.34 v

[tex]Cu^{+2}[/tex]  (aq)  +   2[tex]e^-[/tex]  ------------> Cu (s)             ,     [tex]E_0[/tex]  =  -0.04 v

----------------------------------------------------------------------------------------------

Cd(s)  +  [tex]Cu^{+2}[/tex]  (aq)  ------------->  [tex]Cd^{+2}[/tex] (aq)  +  Cu (s)   ,      [tex]E_0[/tex]  =  0.30 v  

The cell potential is defined as the measure of [tex]\text{ potential difference }[/tex]  between the [tex]\text{two half cells}[/tex] of an electrochemical cell.  

Answer:

B

Explanation:

strong acids ionize completely in water

Answer:

An acid that does not dissolve completely

Explanation:

Answer:

B

Explanation:

During the first half of the reaction there was an increase in the rate of reaction due to the high concentration of the reactants. But as the reaction continues we witness a decrease in the amount of reactants which lowers the rate.

Answer:

B.  The concentration of reactants decreased while the concentration of product increased.

Explanation:

took the test :)

Explanation:

Solubility is defined as a property of solutes by virtue of which they get dissolved in a favorable solvent. The solute can only be dissolved in any suitable solvent up to a limit at a given temperature. This is a characteristic of the the solute-solvent pairing.

Answer:

a) clockwise

b) clockwise and

c) anticlockwise

Answer:

2.76 gram

Explanation:

2AI + 6HCl → 2AlCl3 + 3H2

Answer

Al +2 HCl - AlCl2 + H2

Temperature is measured in Kelvin..

Answer:

3 - a heterogeneous mixture

4- Sweet tea is an homogeneous mixture

Answer:

Explanation:

6. d

7. b

8. c

Answer:

Some examples of solutions are salt water, rubbing alcohol, and sugar dissolved in water. ... In our example of salt water, the solute is the salt. Solvent: this is the substance that makes up the majority of the solution. This is the part where the solute is dissolved.

Explanation:

I hope they should be right answer

Answer:

6

Explanation:

How many valence electrons does this atom have?

answer 6

Answer:

6.

Sulphur has 6 valence electrons.

( .°. that's the electronic configuration of sulphur .)

Answer:

The error includes;

a) The wrong denominator for the equivalent fraction of kilograms to grams

b) The use of the scale factor of length rather than the scale factor of volume for the equivalent fraction of cubic centimeters to cubic meters

c) The arrival at the correct 1000 kg/m³ rather than 0.1 g/m³ based on the expression on the left of the equation

Explanation:

The density of water = 1 g/cm³

The given equation is presented as follows;

1 g/cm³ × 1 kg/(1000 kg) × 100 cm³/(1 m³) = 1000 kg/m³

The error in the conversion method are;

a) The conversion, 1 kg/(1,000 kg) has an error, the correct conversion is (1 kg)/1,000 g)

b) The volume conversion error, 100 cm³/(1 m³), the correct volume conversion is (100 cm)³/(1 m³) = 1,000,000 cm³/(1 m³)

c) The right of the equal to sign error; using the left side expression only, the (wrong) answer is 0.1 g/m³

The correct equation is presented as follows;

1 g/cm³ × 1 kg/(1000 g) × 1,000,000 cm³/(1 m³) = 1000 kg/m³

Answer:

C. 1,000 kg should be written as 1,000 g.

Explanation:

Got it right on my test :)

Answer:

Explanation:

this is the answer hope it helps!(:

The chemical formula of pentanitrogen heptachloride is N₅Cl₇ as it has 5 nitrogen atoms and 7 chlorine atoms.

Chemical  formula is a way of representing the number of atoms present in a compound or molecule.It is written with the help of symbols  of elements. It also makes use of brackets and subscripts.

Subscripts are used to denote number of atoms of each element and brackets indicate presence of group of atoms. Chemical formula does not contain words. Chemical formula in the simplest form  is called empirical formula.

It is not the same as structural formula and does not have any information regarding structure.It does not provide any information regarding structure of molecule as obtained in structural formula.

There are four types of chemical formula:

1)empirical formula

2) structural formula

3)condensed formula

4)molecular formula

Learn more about chemical formula,here:

https://brainly.com/question/29031056

#SPJ2

Answer:

Pb3O4 + 4H2 → 3Pb + 4H2O

Explanation:

Pb3O4

Tritium - H2

Molar Mass of H2 Bond Polarity H-3 Hydrogen-3 3H T

Products

Lead - Pb

Molar Mass of Pb Plumbum Element 82 Bulk Lead

Water - H2O

Molar Mass of H2O Oxidation Numbers of H2O Dihydrogen Monoxide Dihydridooxygen Hoh Hydrogen Hydroxide Dihydrogen Oxide Oxidane Hydrogen Oxide Pure Water

Answer:

Not exactly such but Experimental manipulation describes the process by which researchers purposefully change, alter or influence the independent variables(IVs), which are also called treatment variables or factors in an experimental research design.