Which of the following is a physical change?

Dissolving salt in water

Digesting food

Burning wood

Oxidation

Answer:2 hours

This range of temperatures is often called the "Danger Zone." Never leave food out of refrigeration over 2 hours. If the temperature is above 90 °F, food should not be left out more than 1 hour. Keep hot food hot—at or above 140 °F.

Explanation:

Answer:  Electrons

Explanation:

A chemical reaction usually only affects elctrons. A chemical reaction usually results in the electrons being transferred or shared. When sodium and fluorine react to produce sodium fluoride, a sodium electron is transferred to the fluorine to produce ionic bonds. This ionic bond exists between the sodium cation and fluoride (fluorine) anion.

Answer:

23: 6000560000000

24: 0.0015

25: 200

26: 0.0105

27: 600

28: 4023000

Explanation:

You have to move the decimal the same amount of times as the exponent says.

For example, like with the 6, you move it 2 decimals to the right (since it's positive), and the regular number would be 600.

Answer:

heterogeneous

Explanation:

have you ever started to eat veg soup and begin with a spoon full of broth, no veggies,

Then when you get to the end, there are veggies. no broth.

In a homogeneous  mixture, every sample is the same

in a heterogeneous mixture, the composition changes from sample to sample

Answer:

water and salt

Explanation:

A neutralization reaction is when an acid and a base react to form water and a salt and involves the combination of H+ ions and OH- ions to generate water. The neutralization of a strong acid and strong base has a pH equal to 7.

Hope this helps

PLS MARK BRAINLIEST

Answer:

see explanation

Explanation:

number of moles = mass ÷ relative formula mass

e.g.

Calculate the number of moles of carbon dioxide molecules in 22 g of CO2.

Ar (relative atomic mass) of C = 12, Ar of O = 16

Mr (relative formula mass) of carbon dioxide = 12 + 16 + 16 = 44

number of moles = 22 ÷ 44 = 0.5 mol

Answer:

So the asnwer is 66666666666666666666666666666666666666666666666666666666666666666666666666666666666668888844444444444444444443299997832........................................................4563ygfdjuzgu3456655555555555555555555553444446445444444555554

Explanation:

Answer:

The particle theory of matter is a model that describes the arrangement and movement of particles in a substance. The model is used to explain the physical properties of solids, liquids and gases. Particle arrangement and movement

Explanation:

Answer

No you did not lose weight.

Explanation:

Weight is the force acting on an object, Gravity is a force on earth which does not apply to the moon so your weight may change depending in where you are but your mass will stay the same because mass measures the matter of an object ITSELF! Have a nice day....

Answer:

I would take my weight on Earth and divide it by  6. I'd weigh less because the gravitational pull on the Moon is less, and, weight is the measure of gravitational pull. I wouldn't "loose weight" because I'd weigh the same on Earth  as I did the day I left (give or take a few pounds).

Explanation:

Answer:

hehe I needed some brianliest plz OK

Explanation:

Glucose and galactose are monosaccharides that differ from one another only at position C-4. Thus, they are epimers that have an identical configuration in all the positions except in position C-4. ... Glucose and galactose are epimers that do not differ in position C-5 but differ in position C-4.

Glucose and mannose are epimers that differ at the C-2 carbon, while glucose and galactose are epimers that differ at the C-4 carbon, as shown below. When a molecule such as glucose converts to a cyclic form, it generates a new chiral center at C-1.

Water has a density of 1.0 g/mL. A plastic cup floats when it is placed into a container of water as it is less denser than water.

Density is a key notion in physics and material science that quantifies how tightly packed a substance's particles or molecules are within a certain volume. It is a measure of the mass contained in a certain amount of space that gives useful information about the properties of various materials.

It is vital to highlight that density is a material attribute that remains constant regardless of sample size. A little piece of iron, for example, has the same density as a huge iron block, despite the larger block having more mass.

To know more about density, here:

https://brainly.com/question/29775886

#SPJ3

Answer:

8

Explanation:

It increases going up, because atom size is smaller, with greater energy levels; going right to left decreases, because they will have smaller charges when going through right to left.

Then, Calcium (Ca) is non-metal that reacts with Nitrogen (N), a non-metal. When 2 non-metal elements become a compound, it's covalent. Therefore, the bond between both of the elements are covalent.

Answer:

What is the difference between the crust and lithosphere? The crust (whether continental or oceanic) is the thin layer of distinctive chemical composition overlying the ultramafic upper mantle. ... The lithosphere is the rigid outer layer of the Earth required by plate tectonic theory.

Explanation:

Answer:

b

Explanation:

deposition is the differentiates weathering from erosion

Explanation:

A. Hydrogen bonding is present in CS2 but not in CO2.

B. CS2 has greater dipole moment than CO2 and thus the dipole-dipole forces in CS2 are stronger.

C. CS2 partly dissociates to form ions and CO2 does not. Therefore, ion-dipole interactions are present in CS2 but not in CO2.

D. The dispersion forces are greater in CS2 than in CO2.

PLS MARK BRAINLIEST :D

Answer:

4200

Explanation:

4,000 * .8 + 5,000 * .2

The weighted average of lemonas with 80% GX model and 20 % GXL model is calculated using their mass percent and it is 4200.

What is  weighted average?

The weighted average is different from the normal average we use in maths. Let's X and Y be two number and their average be x+ y/2. That is the arithmetic mean.

The weighted average of lemonas is similar to the atomic weight of an element calculated from ist two isotopes where, the percentage abundance in earth and the mass of isotopes if given the weighted average is calculated as follows:

weighted average =  % abundance / 100 × mass of isotope 1 + % abundance / 100 × mass of isotope 2

In a similar way, the weighted average of lemonas of GX and GXL model is calculated as follows:

weighted average = ( 4000 lbs ×80/100 ) + ( 5000 lbs ×20/100)

                               = 4200 lbs.

Hence, the weighted average of lemonas if 80% are the GX model (4,000 lbs) and 20% are the GXL model is 4200 lbs.

To find more about weighted average, refer the link below:

https://brainly.com/question/28042295

#SPJ2

Answer:

A dunes windward side is the side where the wind is blowing and pushing material up. A dunes slip face is simply the side without wind. A slipface is usually smoother than a dunes windward side. A collection of dunes is called a dune belt or dune field.

Explanation:

Hope this helps...

Answer:

Metallic character increases down each Group of the Table as the outer electrons are further from the nucleus and require less energy for their removal. (a) metallic character decreases from left to right in each Period.

Explanation:

The metallic character increases down each Group on the periodic table.

The metallic character decreases from left to right in each Period.

learn about metallic character,

https://brainly.com/question/16940676

#SPJ2

Answer:

hydrogen bonding

Explanation:

The strongest among them is hydrogen bonding, and the weakest are London dispersion forces.

The strongest intermolecular force to overcome when ethanol is converted from liquid to a gas is hydrogen bonding.

Intermolecular forces are forces that are a weaker force of attraction than intramolecular forces.

Intermolecular forces are forces between molecules and hold these molecules together.

Hydrogen bonding is an example of intermolecular forces between the OH group in the alcohol.

During the conversion of ethanol from liquid to gas state,  hydrogen bonding occurs between the partial negative charge in the oxygen and the partial positive charge in the hydrogen.

Learn more about intermolecular force here:

https://brainly.com/question/13588164

Answer:

Example of a fusion dish: combination of smoked salmon wrapped in rice paper, with avocado, cucumber and crab sticks. Fusion cuisine is cuisine that combines elements of different culinary traditions that originate from different countries, regions, or cultures.

Answer:

It's from the quation:

[tex] \boxed{ \mathsf{ \underline{2K} +\underline{2 H_2O} \rightarrow \:\underline{2}KOH + H_2 }}[/tex]

(How did I know?)

I learnt it while studying the elements of group 1.

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

K, here, is Potassium. It's position in the periodic table is Group 1, Period 4.

Valance electrons of elements of this group contribute to the valency of the group's elements I.e.,

valency of Alkali metals is 1!

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

What are hydroxides?

Hydroxides of an element comprises one atom each of oxygen and Hydrogen bonded together, acting as an anion, the hydorxide anion — OH-.

Example:

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

In the question, The reactants are missing but the products are known, that are, Potassium Hydroxide and water.

Keeping the above mentioned property in mind, the reactants come clear as Potassium(K) and Cold water(H2O).

that makes the equation:

[tex] \mathsf{K + H_2O \rightarrow \: KOH + H_2 }[/tex]

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

For an equation to be balanced, the number of atoms of each elements on both side of the equation must be equal.

Number of atoms of each element on the LHS:

(subscript in front of an atom represents its number of atoms in the compund)

Number of atoms of each element on the LHS:

The number of Hydrogen atoms on boths sides is NOT balanced!

Hit and trial method:

If we add a "2" in front of K, H2O and KOH

[tex] \mathsf{ \underline{2K} +\underline{2 H_2O} \rightarrow \:\underline{2}KOH + H_2 }[/tex]

Number of atoms on both the sides become equal.

(TIP: This comes thru practice:/. but main point is even out the oxygen and Hydrogen atoms first. like if it's 3 multiply it by 2 and you get an even number, I.e., 6)

Number of atoms of each element on the LHS:

Number of atoms of each element on the LHS:

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

Hence, the balanced form of the equation is:

[tex] \boxed{ \mathsf{ \underline{2K} +\underline{2 H_2O} \rightarrow \:\underline{2}KOH + H_2 }}[/tex]

Answer:

nervous tissues

Explanation:

Nervous tissue is found in the brain, spinal cord, and nerves. It is responsible for coordinating and controlling many body activities. ... The cells in nervous tissue that generate and conduct impulses are called neurons or nerve cells. These cells have three principal parts: the dendrites, the cell body, and one axon

credits to the person who provided this info.

Answer:

At 100 °C (the boiling point of water at standard atmospheric pressure), water molecules in the liquid state have a density of 0.9584 g/cm3. This means that there are 3.21 × 1022 water molecules packed into 1 cm3 and the average distance between water molecules is 3.91 × 10-8 cm.

This is what I found. Hope it helps!

Answer:

I think that it would be better to have smaller cells because smaller cells takes less energy to transport waste and generally more efficient to control than larger cells. It is better to have smaller cells because larger and fewer cells takes up more nutrients, but doesn't cover as many surface area. In the end, smaller cells are more efficient, cover more surface area, and moves faster than bigger cells.

Explanation:

I hope that this is the kind of answer you were looking for!