1. an ancient study or art which attempted to combine science and philosophy to solve worldly problems alchemy 2. a homogeneous mixture of elements with metals to form metallic solids alloy 3. the simplest unit of an element that still retains the properties of that element compound 4. two or more elements joined together such that the elements have lost their individual identity element 5. a primary substance that cannot be divided into separate substances metal 6. the group of elements that are good conductors of electricity and heat atom 7. the group of elements that are poor conductors of electricity and heat

Answer:

Explanation:

A

Answer:

Explanation:

Both plastic and gasoline are products of pretroleum

Answer:

1-

A) H2O        B) HCO3-

2-

A) NH3         B) SO3-2

Explanation:

Answer:

V = 16.81 L

Explanation:

Given data:

Number of moles = 0.75 mol

Temperature = standard = 273 K

Pressure = 1 atm

Volume of balloon = ?

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

Now we will rearrange the formula.

V = nRT/P

V = 0.75 mol ×0.0821 atm.L/mol.K ×273 K / 1 atm

V = 16.81 atm.L/ 1 atm

V = 16.81 L

Answer:

2.5 I don't have a explanation

Answer:

3Mg + 2AlCl3 --> 2Al + MgCl2

The source of alpha particles in a smoke detector is the Americium.

Answer:

I think the answer is A. I am only 50% sure I am correct, but hope it helps!

Explanation:

Answer:

d = 20.89 g/cm³

Explanation:

Given data:

Length of block = 4.20 cm

width of block = 3.80 cm

Height of block = 5.40 cm

Mass of block = 1800 g

Density of block = ?

Solution:

First of all we will calculate the volume.

V = l×w×h

V = 4.20 cm ×3.80 cm× 5.40 cm

v = 86.18 cm³

Density:

d =m/v

d =1800 g/ 86.18 cm³

d = 20.89 g/cm³

Answer: i think it is A

Explanation:

hope this helps!

a. The symbol [tex]\tt _{11}^{23}Na[/tex], [tex]\tt _{18}^{40}Ar[/tex], [tex]\tt _{15}^{31}P^{3-}[/tex], [tex]\tt _{13}^{27}Al^{3+}[/tex]

b. Isotope of Na

Atomic number=number of protons=number of electrons(neutral atom)

Number of neutrons=mass number-atomic number

Mass number=protons+neutrons

B. atomic number=11, mass number=11+12=23⇒Sodium

[tex]\tt _{11}^{23}Na[/tex]

C. atomic number=18, mass number=18+22=40⇒Argon

[tex]\tt _{18}^{40}Ar[/tex]

D. atomic number=15, mass number=15+16=31, charge -3(electron-proton)⇒Phosphor

[tex]\tt _{15}^{31}P^{3-}[/tex]

E. atomic number=13, mass number=13+14=27, charge +3(proton-electron)⇒Aluminium

[tex]\tt _{13}^{27}Al^{3+}[/tex]

Isotope=the same atomic mass, different neutron(mass number)

So the atom⇒isotope of Sodium(Na)

Answer:

if a 40.0-gram sample of the gas occupies 11.2 liters of space at STP? A balloon is filled with 5 moles of helium gas.

Explanation:

Answer+Explanation:

Titanium ( in place of iron)

Titanium could be an excellent replacement for iron when it comes to tensile strength versus weight. It would be the first choice as a building material metal and building skeletons/bridges would use titanium instead of iron.

Magnesium alloys (in place of aluminum)

Magnesium alloys potentially met the present demands for lighter and reliable construction. With comparable specific stiffness, higher specific strength and energy absorption magnesium alloys have the potential to replace steel and aluminum alloys.

aluminum (in place of copper)

Most non-copper metal cabling is aluminum, and it is often used in areas where copper is not a likely alternative. However, it is used more now as a replacement than it has ever been. It is cheaper than copper, and its relative density allows for more cable to be made from a ton of aluminum than a ton of copper.

hope it helps you

Answer:

Deposition

Explanation:

Deposition is the phase transition in which gas transforms into solid without passing through the liquid phase. Deposition is a thermodynamic process. The reverse of deposition is sublimation and hence sometimes deposition is called desublimation.

Answer:

A wave with a higher frequency have a shorter wavelength, the higher the sound it, the closer the arcs of the wavelength are, the faster the sound is, the shorter they are.

According to scied.ucar.edu  ~  "The frequency of a wave is inversely proportional to its wavelength. That means that waves with a high frequency have a short wavelength, while waves with a low frequency have a longer wavelength. Light waves have very, very short wavelengths."

Hope this helps

Explanation:

May I have brainliest please? :)

A wave with a higher frequency has a longer wavelength is a false.

A wave with a higher frequency has a longer wavelength is a false statement because shorter wavelength have higher frequency and also higher energy.

We know that longer wavelength of a wave having shorter frequency and shorter energy while on the other hand, the shorter wavelength of a wave having higher frequency and higher energy so we can conclude that the statement is false.

Learn more about frequency here: https://brainly.com/question/254161

Answer:

tell how you feel

Explanation:

don't be afraid to express your feeling.  

Answer:

slowly approach them and tell your feelings

Answer: A

Explanation:

The white Dwarfs are a group of stars that are extremely bright and hot. Hence option A is correct.

Stars are defined as any large gaseous heavenly body that emits light as a result of its own internal energy sources. Stars are celestial bodies that generate their own energy through the fusing of gases. They resemble bright orbs that burn gas and produce energy. Our solar system's star, the Sun, generates energy through the fusion reaction in which helium transforms into hydrogen.

When a white dwarf first forms, it is extremely hot, but because it has no energy source, it will gradually cool as it emits its energy into space. This implies that the color temperature of its radiation, which is initially high, will gradually decrease and turn red. After using up all of their nuclear fuel, stars like the Sun become white dwarfs.

Thus, the white Dwarfs are a group of stars that are extremely bright and hot. Hence option A is correct.

To learn more about stars, refer to the link below:

https://brainly.com/question/7379319

#SPJ2

Answer: 129.93577

Explanation:

There-

Answer:

Your muscles require extra oxygen when you workout, about three times as much as the resting muscles. This need implies that the heart begins to pump harder, which allows for a faster pulse. Your lungs, meanwhile, draw in more oxygen as well, hence the harder breathing.

Explanation:

when you exercise, your heart starts pumping blood faster, which eventually makes your pulse faster.

Answer: -2.1 x 10^10 N

Explanation:

Answer:

Explanation:

Groundwater spread over the years

Answer:a and d

Explanation:

The properties of ionic compounds are hard solids with high melting and boiling points and good conductors of electricity, but only when dissolved in water and the correct options are option A and D.

Ionic solids are made up of ions joined together by ionic bonds. "Ionic bonding" is a type of chemical bond between a positive and a negatively charged ion where the transfer of electrons occurs.

They are too hard, and the ionic solids’ melting point is usually too high due to powerful forces between the anions and cations.

They are known as electrical insulators when they are in a solid-state. Apart from this, the molten salts do behave with electricity since the ions are not closed in the lattice.

Therefore, the properties of ionic compounds are hard solids with high melting and boiling points and good conductors of electricity, but only when dissolved in water and the correct options are option A and D.

Learn more about Ionic solids, here:

https://brainly.com/question/15241125

#SPJ2

Answer:

(SrSe) | SeSr - PubChem.

Explanation:

Answer:

I did this already

................

Answer:

what

Explanation:

I cant see your question yet

Answer:

the question really said :

Answer:

0.0125mol/dm³

Explanation:

Given parameters:

Mass of carbon dioxide  = 0.22g

Volume of water  = 400cm³

Unknown:

Concentration in mol/dm³ =  ?

Solution:

Concentration is the amount of solute dissolved in a solvent.

The formula is expressed as;

    Concentration  = [tex]\frac{number of moles}{volume}[/tex]  

Number of moles  = [tex]\frac{mass}{molar mass}[/tex]

       Molar mass of CO₂   = 12 + 3(16) = 44g/mol

Number of moles  = [tex]\frac{0.22}{44}[/tex]   = 0.0005mol

Now,

             1000cm³  = 1dm³

             400cm³ = [tex]\frac{400}{1000}[/tex]  = 0.4dm³

Insert the parameters and solve;

     Concentration  = [tex]\frac{0.005}{0.4}[/tex]  = 0.0125mol/dm³

*sorry I can't give a full explanation.*

g = 9.8 m/s²

w = m*g

Weight of cat: 55 N = m*9.8

m = 5.61 kg

Weight of dog: 110 N = m*9.8

m = 11.22 kg

There is gravitational potential energy (GPE) acting on the cat since it's at the very top.

GPE of cat = m*g*h = 5.61*9.8*2 = 109.96 J

GPE of dog = m*g*h = 11.22*9.8*0 = 0 J (it's 0 m height because it's on the floor instead of in the tree)

But, if the dog was also 2 m up in the tree, its GPE would be 219.91 J.

As you can see, it's GRAVITATIONAL potential energy is bigger than the cat because it weighs more. Generally, if you were just trying to find the force which is w = m*g (since weight is a force), you would see that the bigger the mass, the bigger the force, and gravity stays the same.

Hope this helped