True or false The atomic number of an element is always more than the mass number of that element.

Answer:the element is potassium

the proton and electron is 19 and the nuetron is 19

Explanation:

Answer:

The atomic number gives the number of protons 19

p = 19

The atomic mass is the sum of the protons and neutrons

p+n = 39 p = 19

Put p into the equation and solve for n the neutrons

19+n = 39

Subtract 19 from both sides

19-19+n = 39-19

n = 20

The number of electons equal the number of protons in a neutral atom. The positive charge equal to the negative charge. The negative charge is the number of electons. This ion has a charge of +1. So solve for the negative charge.

-19+1 = -18

The negative charge is -18 so

e = 18

Answer:

Explanation:

25 yard [3 feet / 1 yard] [12 inches / 1 foot] = 25 * 3 * 12 = 900 inches in 25 yards.

Always put the unit you are going to on top and the unit you are coming from on the bottom.

So in this example, you want to going to feet to start with. That's on top. Yards are on the bottom of the first bracket.  In second bracket feet are on the bottom, inches are what you are going to on the top.

Answer:

Explanation:

16.7 inches [1 foot / 12 inches] [1 yard / 3 feet] Notice how the units cancel each other out. You do have numbers in the denominator. What you get, looks like this

16.7

------

(12 * 3)

16.7 / 36

0.4639 yrds

Answer:

- 10.6° C

Explanation:

Given that,

In the aqueous sucrose solution,

Molality of the solution (m) = 5.7

Freezing point constant (K) = 1.86

To find,

The freezing point of the solution = ?

Method:

To find its freezing point, we will first find out if the solute demonstrates an electrolyte or not.

In case it is not, the van't Hoff factor i.e. ration of particles' concentration denoted by (i) would be taken as 1. So,

ΔT(change in temperature) = i * m * K              (putting the given values)

= 1 * 5.7 * 1.86

= 10.6° C

Thus, the freezing point equals to 0 - 10.6° C = -10.6° C.

Answer:

by the expirement:

In which mix salt with water

Answer:

yes they were made to carry thousands of lb high up

Answer:

A

Explanation:

Two parents are involved in Sexual Reproduction but only one is involved in Asexual Reproduction.

Answer:

chemical reaction between those a b c it's a reaction which occurs when heating

1st part is ure answer --> 2M

Given mass -> 58 grams

mass of NaCl -> 58.44 approx -> 58 any

moles given-> 1 moles

[tex]Molarity = \frac{moles}{vol \: in \: lts} [/tex]

[tex]Molarity = \frac{1}{0.5} = \frac{10}{5} \\Molarity = 2M[/tex]

Answer:

1)Or

d.Sublimation

2)

b.iodine is the solute and alcohol is solvent

3)

a.compostion of solute

Answer:

1) a) centrifugation

OR

b) sublimation

2) a) iodine is the solute and alcohol is solvent

3) a) concentration of soLute

The option which isn't a result of surface tension in water is: c. surface area is maximized.

Water can be defined as a liquid molecule that comprises the chemical element hydrogen and oxygen in the ratio of two to one (2:1).

Surface tension can be defined as a property of liquid such as water, which makes its surface to resist an external force due to the cohesive nature of its molecules.

This ultimately implies that, the surface tension of a liquid is mainly as a result of the cohesive forces existing between its molecules.

Generally, the surface tension of water is typically higher than the surface tension of most liquids.

Due to the effect of surface tension in water;

Additionally, the surface tension of a liquid such as water can be described as an inward force which tends to minimize its surface area rather than maximize its surface area.

In conclusion, surface tension in water doesn't maximize its surface area.

Find more information: https://brainly.com/question/11348644

Answer:

Einstein also in 1905 mathematically proved the existence of atoms, and thus helped revolutionize all the sciences through the use of statistics and probability. Atomic theory says that any liquid is made up of molecules (invisible in 1905)

Explanation:

Answer:

The discoveries of Albert Einstein led to development in the understanding of the atom through the study of quantum mechanics and the electron cloud. In this model, there is still a nucleus with protons and neutrons. But unlike the Bohr model, the electrons exist in a cloud outside the nucleus, much like the fruit around the pit of a peach.

Explanation:

Answer:

Explanation:

Lithium Sulphate

Answer:

Lithium sulfate is a white inorganic salt with the formula Li2SO4. It is the lithium salt of sulfuric acid.

Answer:

H2O + SO2 → H2SO3

Explanation:

H2O + SO2 → H2SO3

Answer:

l think this is the answer .

Answer:

3

Explanation:

sky is high and I am good.

In this problem, we need to find the pH of a buffer (pH = 4.45) that is produced by the reaction of strong acids as HBr that reacts with weak bases as NaC₇H₅O₂ producing its weak acid and a salt, as follows:

HBr + NaC₇H₅O₂ → HC₇H₅O₂ + NaBr

If in the reaction, the limiting reactant is the strong acid, we will produce a buffer (The aqueous mixture of a weak acid and its strong base).

Using Henderson-Hasselbalch equation, we can find the pH of this buffer:

[tex]pH = pKa + log \frac{[NaC_7H_5O_2]}{[HC_7H_5O_2]}[/tex]

Where:

pKa is -log Ka = 4.20

[] could be taken as the moles of each species

After the reaction, the moles of HBr = Moles of HC₇H₅O₂ and the remaining moles of NaC₇H₅O₂ = Initial moles of NaC₇H₅O₂ - Moles of HBr.

Moles HBr:

22.5mL = 0.0225L * (0.200mol/L) = 4.5x10⁻³ moles HBr

Moles NaC₇H₅O₂:

50.0mL = 0.0500L * (0.250mol/L) = 0.0125 moles NaC₇H₅O₂

That means the moles after the reaction of the species of the buffer are:

Moles HC₇H₅O₂ = Moles HBr = 4.5x10⁻³ moles

Moles NaC₇H₅O₂ = 0.0125 moles - 4.5x10⁻³ moles = 8.0x10⁻³ moles

Replacing in H-H equation:

[tex]pH = 4.20+ log \frac{[8.0x10^{-3}]}{[4.5x10^{-3}]}[/tex]

pH = 4.45

Learn more about Henderson-Hasselbalch equation in:

https://brainly.com/question/13423434

Answer:

1.26 g

Explanation:

Number of moles of ascorbic acid = concentration × volume

Concentration = 0.447 M

Volume = 16.00 mL

Number of moles = 0.447 × 16/1000

Number of moles = 7.152 × 10^-3 moles

Number of moles= mass/molar mass

Molar mass of ascorbic acid = 176.1 g/mol

Mass = 7.152 × 10^-3 moles × 176.1 g/mol

Mass = 1.26 g

Answer:

When we shake the branch of a tree the tree possesses a state of motion whereas the fruits and leaves tend to remain in state of rest. Due to this inertia of rest the fruits and leaves get detached from the branch and because of gravity it falls down.

Explanation:

so it's because of the gravity .

The element that will have the lowest electronegativity is an element with a small number of valence electrons and a large atomic radius.

Electronegativity of an element is the ability or power of that element in a molecule to attract electrons to its Valence electrons.  The following are the properties of electronegativity:

Atomic radius of elements increase down a group because of a progressive increase in the number of shells occupied by electrons which increases the size. But it decreases across a period because electrons are accommodated within the same shell leading to greater attraction by the protons in the nucleus.

Learn more about electronegativity of elements here:

https://brainly.com/question/20348681

Answer: Its B the guy above me is correct

Answer:

Opposite.

Water exhibits negative charge near hydrogen, positive near oxygen.

This is why it is OPPOSITE.

Let me know if this helps!

Water is a polar compound because it exhibits opposite charges. Therefore, option C is correct.

The term polar compound is defined as the compound with distinct regions of positive and negative charge, as a result of bonding with atoms such as nitrogen, oxygen, or sulfur.

Water is a polar compound because the covalent bonds between hydrogen and oxygen in the water molecule are polar in nature. Any molecule with lone pairs of electrons around the central atom is polar compound.

In water there are two atoms are present that are oxygen and hydrogen. Hydrogen has positive charge while oxygen has negative charge,

Thus, Water is a polar compound because it exhibits opposite charges, option C is correct.

To learn more about the polar compound, follow the link;

https://brainly.com/question/14752836

#SPJ2

40

Explanation:

because its Saturated

Explanation:

2KCLO3 (s) = 2KCl (s) + 3O2 (g)

Explanation:

Desposition of solid matter in a solution

Taking into account the definition of molecular geometry, the correct option is option d.:  the bond angle of a linear molecule is 180 degrees.

In first place, molecular geometry or molecular structure is the spatial distribution of atoms around a central atom. Atoms represent regions where there is a high electron density, and are therefore considered electronic groups, regardless of the bonds they form.

That is, molecular geometry is the three-dimensional arrangement of the atoms that make up a molecule.

The molecular geometry of an element characterizes some of its physical or chemical properties, such as boiling point, viscosity, and density.

Linear molecules are molecules of the AB₂ type in which the central atom does not have lone pairs. To avoid repulsions between the binding pairs, arrange the B groups as far apart as possible. For that they must oppose each other 180 °.

In summary, linear molecular geometry describes the arrangement of different atoms with 180º bonds.

So, the correct option is option d.:  the bond angle of a linear molecule is 180 degrees.

Learn more about molecular geometry with this example:

Answer:

sodium fusion is changed to sodium sulphide if sulphur is present in the compound

Answer:

The limiting reagent is CuCl

Explanation:

The initial number of moles of aluminum, Al = 4.5 moles

The number of moles of copper, Cu = 6.5 moles

The given chemical reaction is presented as follows;

2Al + 3CuCl → 2AlCl₃ + 3Cu

Therefore, we have, 2 moles of aluminum combine with 3 moles of CuCl produces 2 moles of AlCl₃ and 3 moles of Cu

1 mole of Al will combine with (3/2) moles of CuCl,

Therefore, 4.5 moles of Al will combine with (4.5 × (3/2) = 6.75) 6.75 moles of CuCl

Given that the number of moles of CuCl present is only 6.5 moles which is less than the 6.75 moles required to combine with the 4.5 moles, the 6.5 moles of CuCl limits the amount of AlCl₃ and Cu produced, and therefore the CuCl is the limiting reagent.

Answer:

C.

Explanation:

Answer A is incorrect because a compound doesn't have to be made with only metals.

Answer B is incorrect because that is actually the definition of a pure element.

Answer C is correct because to make a compound, there has to be a chemical reaction where bonds are formed and an entirely new substance is created.

Answer D is incorrect because compounds cannot be separated by physical means.

Hope this helps :D