can anybody help me? ill mark brainliest!!! please ITS TIMED

Answer:

Sodium has 1 valence electron and bismuth has 83 electrons (5 valence electrons)

Explanation:

Answer:

make a new friend if you lose one, Its part of life losing people thats what make us people grow and be more mature.

Answer:A measure of performance of fuel for internal combustion engines. Stated simply, a higher octane rating corresponds to more engine power and less knocking or other pre-ignition problems.

Explanation:

I'm also in chemistry.

Answer:

Explanation:

figure indicating the antiknock properties of a fuel, based on a comparison with a mixture of isooctane and heptane.

Answer:

Elements to the left of the line are considered metals. Elements just to the right of the line exhibit properties of both metals and nonmetals and are termed metalloids or semimetals. Elements to the far right of the periodic table are nonmetals. The exception is hydrogen (H), the first element on the periodic table.

Explanation:

Answer:

looking at its metallic luster

Explanation:

Elements may be classified as either metals or nonmetals based on their properties. Much of the time, you can tell an element is a metal simply by looking at its metallic luster, but this isn't the only distinction between these two general groups of elements. Most elements are metals.

Answer:

H20

Explanation:

Answer:

hope it helped you

Explanation:

H2O (u have to write ✍️no 2 below H.

Answer:

It is A: biochemistry

Explanation: i seen there was no answer so i took a chance and surprisingly got it correct

Answer:

e correct option is all of the above

Explanation:

Answer:

im maybe 80% sure it's hydrogen gas

Answer:

When a metal reacts with dilute hydrochloric acid, it forms a metal chloride salt and hydrogen gas.

Answer:

0.2007 nm

3.57 cm

0.01478 g

8280000 pg

Explanation:

1)200.7 pm

1 picometer is equal to 0.001 nanometer.

1 nm = 1000 pm

200.7 pm× 1 nm / 1000 pm  = 0.2007 nm

2)0.000357 hm

1 hectometer is equal to 10,000 centimeter.

1 hc = 10,000 cm

0.000357 hc× 10,000 cm / 1 hc = 3.57 cm

3) 14.78 mg

1 gram is equal to 1000 milligram.

1 g = 1000 mg

14.78 mg × 1 g/1000 mg = 0.01478 g

4)8.280 µg

1 microgram is equal to 10⁶ picogram.

1 µg = 1000000 pg

8.280 µg× 10⁶ pg/ 1µg = 8.280×10⁶ pg or 8280000 pg

Answer:

I think its b. if not sorry but its the one that makes most sense

Explanation:

Answer:

B

Explanation:

Hope this helps you have a nice day!

Answer:

volume of 200mL, density shows it weighs .789 grams for every mL.  .789*200= 157.8 grams

Explanation:

Answer:

Because too much Carbon Dioxide can kill us.

Explanation:

Answer:

1- if one component in a series circuit fails, then all the components in the circuit fail because the circuit has been broken.

2-  the more components there are in a series circuit, the greater the circuit's resistance

Answer:365 days, 5 hours, 59 minutes and 16 seconds.

Answer:

a. homogenous

Answer:  A. homogeneous

Explanation: A mixture that is uniformly mixed is called homogeneous.

Plz mark brainliest:)

Answer:

2, 3, 4, 5

Explanation:

Pretty sure protons matter a lot unless in acid and bases but ignore this. Atoms mostly empty space as electrons are reeeeeeeeeeaaaallllllyyyy far apart. number of electrons change it is an ion and neutrons change pretty sure its an isotope. Electrons are stupidly small and fast so they don't really count towards the weight. Most mas comes from neutrons and protons in the nucleus

Answer:

2,3,4,5

1st is wrong cuz if u change the number of proton it would change the atomic number which results in different element

6th is wrong because most mass of the atoms come from neutrons and protons collectively so if it would have said THE ATOMS MASS MOSLTY COMES FROM NUCLEONS then u could mark it right

D: the thermal energy is moving from the ice cube into the water causing the temperature of the water to decrease.​



Answer:

it is C

Explanation:

I saw from Google. Hope it helps.

I cant get the full picture

sorry

Answer:

2.41×10²³ molecules of water

Explanation:

Given data:

Mass of methane = 3 g

Molecules of water formed = ?

Solution:

Chemical equation:

CH₄ + 2O₂    →     CO₂  + 2H₂O

Number of moles of methane:

Number of moles = mass/ molar mass

Number of moles = 3 g/ 16 g/mol

Number of moles = 0.2 mol

Now we will compare the moles of water with methane.

               CH₄           :              2H₂O

                  1              :                  2

                0.2            :             2 × 0.2 = 0.4 mol

Molecules of water:

1 mole = 6.022×10²³ molecules of water

0.4 mol ×6.022×10²³ molecules of water / 1mol

2.41×10²³ molecules of water

Answer:

i think its D

Explanation:

The law of conservation of mass or principle of mass conservation states that for any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as the system's mass cannot change, so quantity can neither be added nor be removed.

Taking into account the law of conservation of mass,

The Law of Conservation of Matter is also called the law of conservation of mass or the Law of Lomonósov-Lavoisier. This law postulates that "The mass is not created or destroyed, only transformed."

This means that the reagents interact with each other and form new products with different physical and chemical properties than those of the reagents. And this is because the atoms of the substances are ordered differently.

But the quantities of the masses involved in a given reaction must be constant throughout it, that is, they will not have changed in their proportions when the reaction ends. Then the mass before the chemical reaction is equal to the mass after the reaction.

The exception to the rule is nuclear reactions, in which it is possible to convert mass into energy and vice versa.

Finally, the correct answer is option A. because the atoms of the substances are ordered differently, this is the reagents interact with each other and form new products.

Learn more about law of conservation of mass:

Answer:

it is alkali

Explanation:

hope it helps you

Answer:

the brain

Explanation:

[tex]1 \: mol MgSO4 \: has \: 4 \: oxygens[/tex]

Thus ;

[tex]2 \: mols \: of \: should \: have \: 8 \: oxygens[/tex]

So the correct answer is (( 8 مول ))

Ti is a transition metal.

Chemical symbol represent element or compound

The elements are arranged in the periodic system

This is the atomic number of Titanium

The Atomic Number (Z) indicates the number of protons of an element

This is the symbol (chemical formula) of titanium

This is the mass number of Titanium

Mass Number (A) = Number of protons + Number of Neutrons

Atomic Number (Z) = Mass Number (A) - Number of Neutrons

This is the name of the element

To determine which group, alkaline, alkaline earth or transition it can be seen from the electron configuration

alkali and alkali earth : configuration from orbital 1s-7s

transition : configuration from orbital 3d-6d (Block d)

Electron configuration from Ti : [Ar] 3d²4s²

if we look at the configuration, then Ti is in the d block which is included in the transition metal

Answer:

The answer is 26

Explanation:

I just took the test

Answer:

Chemical Change

Explanation:

The explosion of fireworks is an example of chemical change. During a chemical change, substances are changed into different substances. In another words, the composition of the substance changes.

Answer:

A. cars, submarines, spacecraft

Explanation:

I took the test.

Answer:

B. Electrons have the most mass of the

subatomic particles

Compared to the mass of neutron and proton, mass of electron is negligible.

Answer:

B

Explanation:

when creating a Bohr model, you will usually mark protons + or P and neutrons are usually 0 or N.

Electrons are on the rings surrounding the nucleus, but everything else is inside.

Electrons are typically represented by - or E