Although no blueprints of the pyramids have been found, what evidence suggests humans, not aliens, built the pyramids?

Answer:

5%

Explanation:

Given parameters:

Mass of calcium chloride  = 5g

Mass of water  = 95g

Unknown:

Mass percent of calcium chloride in solution  = ?

Solution:

The mass percentage is the mass of the solute component divided by the total mass of the mixture multiplied by 100%.

So;

Mass of mixture  = mass of calcium chloride + mass of water  = 95g + 5g  = 100g

Mass percentage of calcium chloride  = [tex]\frac{5}{100}[/tex] x 100  = 5%

Answer:

"The number of air molecules above a surface determines air pressure. As the number of molecules increases, they exert more pressure on a surface, and the total atmospheric pressure increases. By contrast, if the number of molecules decreases, so too does the air pressure."

The heat released by reaction : C) -8870 J

Given

1.008 g of hydrogen

500.00 g water

The temperature rises 25.00 °C to 29.24 °C

Required

energy required

Solution

Q absorbed by water :

Q = m.c.Δt

Q = 500 g x 4.18 J/g C x (29.24-25)

Q = 8870.08 J

The reaction to produce HCl is an exothermic reaction (releasing heat), so that Q is negative

Q water = -Q HCl = -8870.08 J

On the surface, weathering and erosion break down the igneous rock into pebbles, sand, and mud, creating sediment, which accumulates in basins on the Earth's surface. As successive layers of sediment settle on top of one another, the sediment near the bottom is compressed, hardens, and forms sedimentary rock.

Answer:

A I think

Explanation:

Answer:

I am definitly sure that the answer is C

Explanation:

potential energy is the energy possessed by a body by virtue of its position relative to others, stresses within itself, electric charge, and other factors.

Answer:

Green chemistry

Explanation:

Green chemistry is the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances. Green chemistry applies across the life cycle of a chemical product, including its design, manufacture, use, and ultimate disposal(EPA, 2017).

Green chemistry, also called sustainable chemistry, is an area of chemistry and chemical engineering focused on the design of products and processes that minimize or eliminate the use and generation of hazardous substances(wikipedia).

Thus, any research in chemistry geared towards waste reduction(such as  more efficient methods of paper recycling) and recycling of other materials as well as placing less demands on the natural sources of materials is known as green chemistry or sustainable chemistry.

Answer:

i dont no......

Explanation:

...........

Answer:

0.625

Explanation:

i hope this is correct! and that it helps!! c:

Answer:

Explanation:

...

Answer:

The water cycle, also known as the hydrologic cycle or the hydrological cycle, describes the continuous movement of water on, above and below the surface of the Earth. The mass of water on Earth remains fairly constant over time but the partitioning of the water into the major reservoirs of ice, fresh water, saline water and atmospheric water is variable depending on a wide range of climatic variables. The water moves from one reservoir to another, such as from river to ocean, or from the ocean to the atmosphere, by the physical processes of evaporation, condensation, precipitation, infiltration, surface runoff, and subsurface flow. In doing so, the water goes through different forms: liquid, solid (ice) and vapor. Hope this helps, mark as brainliest please!

Even a small sample of matter may contain millions and millions of atoms, molecules or ions. To represent these entities the unit mole is used. The number of moles in 0.800 g of CaCl₂ is

One mole of a substance is defined as that amount of it which contains as many particles or entities as there are atoms in exactly 12 g of Carbon - 12 is called the mole.

The equation which is used to calculate the number of moles is:

Number of moles (n) = Given mass / Molar mass

The mass of one mole of molecules of a substance is called the molar mass.

Here the given mass of CaCl₂ is 0.800 g and the molar mass is 110.98 g/mol. Then,

n = 0.800 g / 110.98 g / mol = 0.0072 mol

Thus the number of moles is 0.0072 mol.

To know more about moles, visit;

https://brainly.com/question/15209553

#SPJ2

Answer:

I think air is more denser than oxygen

Answer:yeet

Explanation:more yeet

Answer:

stationary is the answer

Explanation:

hope this helps u

Answer: The pressure in atmospheres is 0.674 in the container if the temperature remains constant.

Explanation:

Boyle's Law: This law states that pressure is inversely proportional to the volume of the gas at constant temperature and number of moles.

[tex]P\propto \frac{1}{V}[/tex]     (At constant temperature and number of moles)

[tex]P_1V_1=P_2V_2[/tex]  

where,

[tex]P_1[/tex] = initial pressure of gas  = 205 kPa

[tex]P_2[/tex] = final pressure of gas = ?

[tex]V_1[/tex] = initial volume of gas  = 4.0 L

[tex]V_2[/tex] = final volume of gas = 12000 ml = 12 L    (1L=1000ml)  

[tex]205\times 4.0=P_2\times 12[/tex]  

[tex]P_2=68.3kPa=0.674atm[/tex]        (1kPa=0.0098atm)

Therefore, the pressure in atmospheres is 0.674 in the container if the temperature remains constant.

Answer:

P2=68.33 mm Hg

Explanation:

P1V1=P2V2

PLUG IN

CONVERT mL TO L (12000mL=12L)

(205)(4)=(P2)(12)

DIVIDE BOTH SIDES BY 12

P2= 68.33 kPa

Answer: It is B

Explanation:

EAZYYYY

Answer: A

Explanation: because It shows how they mark there territory by unreining

Answer: O A. Rhinoceros males urinate to mark the area where they live.

Explanation:

O B. Is an example of animals working to together.

O C. This is competition rather than defending territory.

O D. Again an example of animals working together.

Make sure to study, as the text provided for A. P. E. X is extremely helpful! Don’t stress, make sure to stay hydrated, have self care, and remember self care isn’t just proper hygiene make sure you take care of your well being while making sure you’re mindful that you are just a person, have a good day! I love ya’ll and I’m proud of ya!

To clarify the answer is correct as I have the same Test (CST): Response to Stimuli:

Answer:

A. manganese change from +7 to +2

Explanation:

Reduction means a gain of electrons, which means the oxidation number will go down or the charge goes down basically or become more negative charge. On the left, Mn has +7 in MnO4-. On the right, it has 2+, so it has been reduced.

Answer:

Total

Hxbdvdbdj

125 grams

Answer:

2FeCl2+Cl2→2FeCl3

Explanation:

The volume of O₂ : 21 L

Given

8.7 grams of C₂H₄

Required

Volume O₂

Solution

Reaction

C₂H₄ + 3 O₂ ⇒ 2 CO₂ + 2 H₂O

mol C₂H₄(MW= 28 g/mol) :

= mass : MW

= 8.7 g : 28 g/mol

= 0.311

From the equation, mol  O₂ :

= 3/1 x mol C₂H₄

= 3/1 x 0.311

= 0.933

At STP, 1 mol gas=22.4 L, so for 0.933 mol :

= 0.933 x 22.4 L

= 20.899 L ≈ 21 L

Explanation:

it is the one you have selected because it is the only solid one

Answer:

The student is Incorrect

Explanation:

Even if you break a magnet the poles still remains same. There is no

difference in the magnet Both north  and south pole will be there even if you

cut it in to small pieces when you cut it into pieces, if suppose you  break 2

magnets and put north and north together it will repel whereas if there  are  

different  poles like north and south it will attract, so even if you break one

single magnet the different poles will attract, Hence the student is incorrect.

Please mark me as brainliest

Answer:

I can't draw but you could draw 2 electrons in the first orbit and 3 electrons in the second orbit.

Explanation:

Answer:

Your talking about this correct?

Explanation:

Answer:

b.a convex lens forms a smaller,real image.

Answer:

C

Explanation:

Electrons are negatively charged with a charge of -1e. They can move between atoms while protons stay in the atom.

Answer:

See explanation

Explanation:

For SCl2

S = 2.8, Cl = 3.16 difference = 0.4 polar

H2S

H = 2.2  S= 2.8  difference = 0.6  polar

CF4

C = 2.55,  F= 3.98 difference = 1.43

This compound is nonpolar irrespective of the difference in electronegativity because the molecule is symmetrical

PCl5

P= 2.19,  Cl= 3.16  difference = 0.97

This compound is nonpolar irrespective of the difference in electronegativity because the molecule is symmetrical

CH4

C = 2.55    H = 2.2    difference = 0.35 the molecule is nonpolar

CaBr2

Ca= 1    Br= 2.96  difference = 1.96

The compound is not just polar but ionic in nature due to large electronegativity difference between the bonding atoms

SF2

S = 2.8   F= 3.98     difference = 1.18

The molecule is polar

CO2

C= 2.55    O= 3.44  difference = 0.89

This compound is nonpolar irrespective of the difference in electronegativity because the molecule is symmetrical

NH3

N= 3.04     H = 2.2    difference =0.84

The molecule is polar

NaS

Na= 0.93   S = 2.8    difference = 1.87

The compound is not just polar but ionic in nature due to large electronegativity difference between the bonding

Answer:

Mass = 5.92 g

Explanation:

Given data:

Volume of O₂ = 4.15 mol

Temperature and pressure = standard

Mass in gram = ?

Solution:

The given problem will be solve by using general gas equation,

PV = nRT

P= Pressure

V = volume

n = number of moles

R = general gas constant = 0.0821 atm.L/ mol.K  

T = temperature in kelvin

By putting values,

1 atm × 4.15L = n ×0.0821 atm.L /mol.K × 273.15 k

4.15 atm.L = n ×22.43 atm.L /mol

n = 4.15 atm.L / 22.43 atm.L /mol

n = 0.185 mol

Mass in gram:

Mas = number of moles × molar mass

Mass = 0.185 mol ×32g/mol

Mass = 5.92 g