plzzzzzzzz helpppp

The half-life of a radioactive isotope is 2.4 minutes. If you started with 100.0 grams, how many grams would be left after 7.2 minutes has elapsed? Explain how you arrived at your answer.

Answer:

In many parts of the world, water taken directly from wells or public supplies is not safe to drink because it may carry waterborne parasites or other diseases. The water can be sterilized by boiling it, but fuel is needed to do so.

Explanation:

Answer:  Public water supplies are unsafe in some parts of the world because the water may carry bacteria.

Explanation:

Answer:

One mole of H2O corresponds to 18 g .

A water heater can be regularly maintained by flushing it at least two times in a year.

A water heater is a device that is used to heat up water for home use. There are different types of water heaters but they all serve the same purpose at home. In order to maintain maximum efficiency, the water heater must be maintained regularly.

The following are routine maintenance operations on a water heater;

Learn more about water heater;https://brainly.com/question/4751630

The amount remaining at the end of 5 half-lives is 7.81×10¹³ g

From the question given above, the following data were obtained:

The amount remaining can be obtained as follow:

N = 1/2ⁿ × N₀

N = 1/2⁵ × 2.5×10¹⁵

N = 1/32 × 2.5×10¹⁵

N = 0.03125 × 2.5×10¹⁵

N = 7.81×10¹³ g

Therefore, the amount remaining after 5 half-lives is 7.81×10¹³ g

Learn more about half-life: https://brainly.com/question/25783920

Answer:

3, why because most of the time chemicals reacts within eachother to make new compound that's may lead the liquid chemicals to deflect some of the spectrom of light like red,yellow,blue

To solve such this we must know the concept of chemical reaction. There are so many ways to identify the chemical reaction. Therefore the correct options are option 3, 5.

Chemical reaction is a process in which two or more than two molecules collide in right orientation and energy to form a new chemical compound. The mass of the overall reaction should be conserved that is mass can nether be created nor be destroyed in a chemical reaction.

There are so many types of chemical reaction reaction like combination reaction, double displacement reaction. The evidence of a chemical reaction are  "the liquid turned pink when mixed" and "over time, a white solid formed at the bottom of the beaker".

Therefore the correct options are option 3, 5.

Learn more about the chemical reactions, here:

brainly.com/question/3461108

#SPJ5

Answer:

Coffee Filter.

Tea-bags.

Water Filters.

Sand Filtration.

HEPA Air Filters.

Automotive Filters.

Belt Filters.

Dialysis.

Explanation:

The electrons present in the valence shell of an atom are responsible for the reactivity of atoms.

An atom is defined as the smallest unit of matter which forms an element. Every form of matter whether solid,liquid , gas consists of atoms . Each atom has a nucleus which is composed of protons and neutrons and shells in which the electrons revolve.

The protons are positively charged and neutrons are neutral and hence the nucleus is positively charged. The electrons which revolve around the nucleus are negatively charged and hence the atom as a whole is neutral and stable due to presence of oppositely charged particles.

Atoms of the same element are similar as they have number of sub- atomic particles which on combination do not alter the chemical properties of the substances.

Learn more about atom,here:

https://brainly.com/question/13654549

#SPJ2

Answer: im pretty sure its D

Explanation:

Answer:

D

Explanation:

braineist pls???????????

Answer:

C

Explanation:

gram is bigger than atom duh

Answer:

a

Explanation:

Answer:

Im pretty sure it's B, almost 100% sure

Explanation:

Answer: A increase

Explanation: The temperature of room will increase. If a refrigerator door is open then more flow rate of coolant is required in order to maintain lower temperature So the compressor will be running continuously also heat exchange happening through condenser increases the room temperature rather than decreasing.

Answer:

A polar bond is one where the charge distribution between the two atoms in the bond is unequal. A polar molecule is one where the charge distribution around the molecule is not symmetric. It results from having polar bonds and also a molecular structure where the bond polarities do not cancel.

Explanation:

Answer:

0.185moles

Explanation:

1mole of bicarbonate produces 1mole of CO2

so 0.185 mole produces 0.185 moles of CO2

Answer:

20.03g

Explanation:

This is the formula for percentage yield:

Percentage yield = Actual Yield / Theoretical yield

Rearrange it to get the Actual yield, which would be:

Actual yield = Percentage yield (in decimal form) x Theoretical yield

We know that 75% of CO2 is produced as the percentage yield in a reaction and the theoretical yield for the mass we're supposed to find is 26.7 grams.

Percentage yield in decimal form: 0.75

Theoretical yield: 26.7g

Plug it in the equation

Actual yield = 0.75 x 26.7g

Actual yield = 20.03g

Let's check the equation

[tex]\\ \sf\longmapsto {CH_4\atop 1mol}+{4S\atop 4moles}\longrightarrow {CS_2\atop 1mol}+{2H_2S\atop 2moles}[/tex]

[tex]\\ \sf\longmapsto 10.6(0.25)=2.65moles\:of\:CS_2[/tex]

State the given:

Moles of Sulfur = 5 moles

Molar mass of Sulfur = 32.06g/mol

Look through the formulas:

Moles = Mass/Molar Mass

Rearrange the equation:

Mass = Moles x Molar mass

Plug in your given:

5 moles Sulfur   x   32.06g

                                 1 mol

= 160.3g of Sulfur

Answer:

B a shared pair of electrons (2)

Explanation:

In Lewis structures, a single line represents a single pair of electrons. This means that the elements share 2 electrons or one pair of electrons

Hope this helps!

The shared electrons behave as if they belong to both atoms in the bond and bind the two atoms together to form a molecule. The shared electrons are typically depicted as a line (—) connecting the bonded atoms. (A line in a Lewis structure represents two electrons. Therefore, option A is correct.

Lewis structures, also known as Lewis dot formulas, Lewis dot structures, electron dot structures, or Lewis electron dot structures, are diagrams that depict the bonding between atoms in a molecule as well as any lone pairs of electrons that may exist.

A Lewis structure is based on the octet rule, which states that atoms share electrons in order for each atom to have eight electrons in its outer shell. An oxygen atom, for example, has six electrons in its outer shell.

Gilbert N. Lewis, who introduced the Lewis structure in his 1916 article The Atom and the Molecule, was named after it. Lewis structures expand on the electron dot diagram concept by adding lines between atoms to represent shared pairs.

Thus, option A is correct.

To learn more about lewis structure, follow the link;

https://brainly.com/question/4144781

#SPJ6

The strongest intermolecular bonding in ethanol is hydrogen bonding.

Intermolecular forces are the forces that hold two molecules of a substance together in a given state of matter. For ethanol, the strongest intermolecular force is hydrogen bonding.

Hydrogen bonding occurs when hydrogen is directly linked to a highly electronegative element such as oxygen, nitrogen, fluorine or sulfur. The existence of intermolecular hydrogen bonds accounts for unusual properties such as abnormally high melting and boiling points.

Learn more about intermolecular forces: https://brainly.com/question/17111432

neon and xenon are the elements that has similar properties to helium

Answer:

5.21

Explanation: You can only have 3 digits, so you would round to the hundredths place

paper chromatography, in analytical chemistry, technique for separating dissolved chemical substances by taking advantage of their different rates of migration across sheets of paper..The method consists of applying the test solution or sample as a spot near one corner of a sheet of filter paper.

[tex]\large\sf\red{♡♡}[/tex]

Answer:

decreasing

Explanation:

from left to right the nuclear effective charge is increasing, attracting with a greater force the electrons and making the atom to reduces itd atomic radius

The atomic radius decreases along a period in periodic table.  Thus, from the third element Li to the 9th element fluorine, atomic radius decreases and F has the lowest radius among them.

Atomic radius is the distance from the  nucleus to the valence shell. The atomic radius decreases from left to right in periodic table. Thus, the higher atomic radius is exhibited by metallic elements.

The horizontal rows in the periodic table is called periods. Along a period , atomic radius decreases and electronegativity increases. When moving to the right there is no increase in the number of shells and the filling of electrons does not achieve octet except for group 18. Hence, they are electronegative.

From atomic number 3 to 9 atomic number is decreasing. Hence, among these elements, the smallest one is fluorine (Z = 9).

To find more on atomic radius, refer here:

https://brainly.com/question/14544878

#SPJ5

La energía cinética está relacionada con la velocidad de las partículas.

Sabemos que la velocidad de las moléculas de gas depende de la temperatura del cuerpo. La temperatura de un cuerpo es una medida de la energía cinética promedio de las moléculas del cuerpo.

Debemos notar que cuanto mayor es la temperatura del cuerpo, mayor es la velocidad de sus moléculas. Por lo tanto, a una temperatura de 10,000,000 ° C, las moléculas en el núcleo del sol tienen una velocidad mayor que las moléculas en la superficie del sol.

Todas las moléculas, ya sea en el núcleo o en la superficie del sol, se mueven a mayor velocidad que las moléculas de la limonada a una temperatura mucho más baja. La energía cinética está relacionada con la velocidad de las partículas.

Obtenga más información sobre la energía cinética: https://brainly.com/question/11067389

Answer:

38 pounds of gold in cubic mile of seawater.

Answer:

On the periodic table, electronegativity generally increases as you move from left to right across a period and decreases as you move down a group. As a result, the most electronegative elements are found on the top right of the periodic table, while the least electronegative elements are found on the bottom left.

Explanation:

Answer:

on the periodic table, electronegativity generally increases as you move from left to right across a period and decreases as you move down a group. As a result, the most electronegative elements are found on the top right of the periodic table, while the least electronegative elements are found on the bottom left.

Explanation:

hope this helps!

Answer:

A tumor

Explanation:

Answer:

It's Cancer

Explanation:

I did this before.

Answer:

Explanation:

P = Physical Change

C = Chemical Change

water boiling                         P

a car rusting                           C

petrol burning                          C

beer fermenting                        C

ice cream melting                   P

wind blowing                               P

milk turning sour                             C

seawater evaporating                 P

sugar dissolving in tea                 P

food being digested                         C

bleach cleaning a dirty cloth