Please help brainiest

Answer:

2.

63.9 cm2

Explanation:

All non-zero digits are consider significant figures like 1, 2, 3, 4, 5, 6, 7, 8, 9.

Leading zeros are not consider as a significant figures. e.g. 0.06 in this number only one significant figure present which is 6.

Zero between the non zero digits are consider significant like 108 consist of three significant figures.

The zeros at the right side e.g 240000 are also significant. There are six significant figures are present.

When we add or subtract the values the number of significant figures after decimal in result must be equal to the given measurement having less number of decimal places.  For example,

The difference between 7.69 and 4.0.

7.69 - 4.0 = 3.7

When we multiply or divide the values the number of significant figures must be equal to the less number of significant figures in given value.

For example in given q:

52.6 cm × 1.214 cm = 63.9 cm²

Answer:

The periodic table is organized in non-metals metals and metalloids, in in terms of trends and patterns you may want to talk about the the density of the elements or the mass of per unit of measurement of whatever you're going to use sorry that could be much help but I hope it helps.

It is incorrect because it should have a total of eight electrons with two electrons between each H and O

Lewis structure shows the form of bonds that occur in the valence electrons of an element or compound

This bonding usually occurs in covalent bonds

Valence electrons are electrons used in a chemical bond

The main group elements usually have valence electron configurations in the ns and np subshells, While the transition elements in the subshells (n-1) d and ns.

Element O has 6 valence electrons

Element H has 1 valence electron

To achieve stability, the element O needs 2 more electrons which are obtained from 2 electrons from the H element, while the H element needs 1 electron to be stable

So that a covalent bond is formed

Answer:

/D/ either absorbs or releases energy

Explanation:

During a phase change energy is either absorbed or released.

A phase change is a reversible process which occurs when a substance changes is its state from one form to another.

Phase changes are used to delineate physical changes.

Answer:

Explanation:

Convert mass in gms .. 987 gms

Density = mass/ volume

= 987/4.52 x102

= 2.18 g/mL

Answer: The solid turns into liquid during melting.

Explanation:

a. The process of a solid turning into liquid is called melting. The solid ice turns into a liquid during the melting process. The solid molecules gain energy and flow as a liquid.

b. The energy of the molecules increases in the liquid state. When the ice turns into a liquid the energy of the molecules increases. The application of heat or excess temperature increases the energy of the molecules.

Answer:

D

Explanation:

( I hope that this helps )

Answer:

The answer is d

Explanation:

Answer:

4.00 g/mL

Explanation:

Density is mass divided by volume (g/mL).

Mass of rock = 21.58

Volume of rock = 25.4 - 20.0 = 5.4mL

Density of rock = 21.58g / 5.4mL = 3.99629 g/mL

Round to the lowest number of significant figures which is three = 4.00 g/mL

Answer:

26.1g

Explanation:

Cclf3

=35.5

F=54/101.5

Mass=mol*mm

=0.25*1015

=26.1g

Answer:

Ionic bonding is the complete transfer of valence electron(s) between atoms. It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion

Explanation:

pleaseee mark brainliest <3!

Answer:

A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and plus and minus signs. These are limited to a single typographic line of symbols, which may include subscripts and superscripts. A chemical formula is not a chemical name, and it contains no words. Although a chemical formula may imply certain simple chemical structures, it is not the same as a full chemical structural formula. Chemical formulae can fully specify the structure of only the simplest of molecules and chemical substances, and are generally more limited in power than are chemical names and structural formulae.

Explanation:

Have A Wonderful Day !!

Answer:

Mineral acids are very important to chemical procedures. An organic acid is an organic compound with acidic properties. ... Generally, organic acids are weak acids and do not dissociate completely in water, whereas the strong mineral acids do.

Answer:

Organic Acids:

Mineral Acids:

Answer: A.

Explanation:

The molecular formula for glucose is C6H12O6. This means that there are 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms bonded together to make one molecule of glucose.

Hopes this helps!

Answer:

b

Explanation:

Answer

Explanation:

an atom is usually define as a perfect balance of electrons and protons

Answer:

The empty cup

Explanation:

Got it right on the test

Answer:

magnesium. stronsium. barium. they are have similar group in IIA

Answer:

sulfide is S 2- so it will be M 2+

Answer:

They are in the same family, with similar characteristics.

Explanation:

The elements in a given group of the periodic table are in the same family and with similar characteristics.

Answer:

false

Explanation:

Hope the answer was usefull for us

Answer:

false. there is the surface soil, which has a lot of partly decayed stuff, topsoil, which has minerals and organic material, subsoil, which is made from sand, silt, and clay that hasn't been broken down, and parent material, which is the place where not much living things live in, except for gigantic tree roots. then there is the bedrock, which is; you guessed it:rock entirely.

Explanation:

Answer:

A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and plus (+) and minus (−) signs.

Compounds used as medicines are most often organic compounds, which are often divided into the broad classes of small organic molecules (e.g., atorvastatin, fluticasone, clopidogrel) and "biologics" (infliximab, erythropoietin, insulin glargine), the latter of which are most often medicinal preparations of proteins

Explanation:

Answer: The water vapor transfers thermal energy to the air.

Explanation:

Answer:

Rubidium= [Kr] 5s^1

Calcium= [Ar] 4s^2

Aluminium= [Ne] 3s^2 3p^1

Explanation:

A noble gas configuration begins with the elemental symbol of the last noble gas prior to the atom. The symbol is then followed by the remaining electrons.

Hope this helped! good luck :)

Answer: Christy won Molly by 12cm

Explanation:

Ist step

Molly's ;ong jump was 118.3cm

Christy long jump was 51.18inches

2nd Step

we change christy score to cm so we can compare

1 inch = 2.54cm.

therefore 51.18 inches = 51.18 x 2.54= 129.9972cm

Christy won molly by 129.9971cm-118.3cm=11.69 rounded to 12cm

Christy won Molly by 12cm

you can see the answer at the pic

Answer:

The mechanical energy of the system increases, provided there is no loss of energy due to friction. The energy would transform to kinetic energy when the speed is increasing. The mechanical energy of the system remains constant provided there is no loss of energy due to friction.

Explanation:

Answer:

You could have a scratch test, fog test, break test, theres many tests you could perform to see if it is a diamond.

Explanation: