1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Ksju [112]
3 years ago
10

Changing the number of protons in an atom makes A. an ion B. an isotope

Chemistry
1 answer:
lana [24]3 years ago
5 0
A. an ion

The atom gains a net electrical charge if the number of protons and electrons are not equal which makes it an ion.
You might be interested in
10. Air is a homogenous mixture of gases. Oxygen is 20% by volume of air typically. What
raketka [301]

Answer:

893 moles

Explanation:

An ideal gas at STP occupies 22.4 liters. Calculating Oxygen as if it were an ideal gas there are . 893 moles of Oxygen in 20.0 liters.

3 0
2 years ago
How much heat is required to change the temperature of two cups of water (500 g) from room temperature (25◦C) to boiling? Specif
NNADVOKAT [17]

Answer:

c. 157 KJ

Explanation:

Q= mC dT    dT= 100°C(boiling point) - 25°C=75°C

Q= (500 g * 4.184 J/g °C * 75 °C)

Q= 156900 J= 157 KJ

6 0
2 years ago
What is valence of helium​
AnnZ [28]
The valence of helium is 0.
5 0
2 years ago
Read 2 more answers
Reaction of 0.028 g of magnesium with excess hydrochloric acid generated 31.0 mL of hydrogen gas. The gas was collected by water
MA_775_DIABLO [31]

Explanation:

(a)   It is given that magnesium is reacted with hydrochloric acid and the hydrogen evolved is collected at top. This means that hydrochloric acid will be present in a solution (HCl + Water) and the solvent will be water.

Due to evaporation some amount of water will have evaporated and would be present in vapor phase. Therefore, when the reaction occurs only hydrogen will not be present in vapor phase but, will be accompanied by water vapors as well .

Hence, Dalton's law the total pressure of the system will be sum of pressure exerted by hydrogen gas and pressure exerted by water vapors .

Let us assume that the partial pressure of hydrogen gas be "P_H_{2}"

And, the partial pressure of water will be nothing but the vapor pressure of water,

Vapor pressure of water = P_{water}

                                         = 19.8 mm Hg

Total pressure of the system = 746 mm Hg

Total pressure = P_H_{2} + P_{water}

               746 = P_H_{2} + 19.8

or,               P_H_{2} = 746-19.8

                                = 726.2 mm Hg

Hence, partial pressure of hydrogen gas is 726.2 mm Hg.

(b) To calculate volume at STP, we will first calculate at 22^{o}C and 726.2 mm Hg and than convert it to STP conditions.

Therefore, to calculate volume at 22^{o}C and 726.2 mm Hg we will make use of ideal gas law  as follows.

           P = 726.2 mm Hg

             = \frac{726.2}{760}

             = 0.955 atm

          T = 22^{o}C

              = 22+273.15 = 295.15 K

         V = 31 ml = 31 \times 10^{-3} Litre

According to the ideal gas law ,

              PV = nRT

where,      P = pressure of the system ,  

                 V = volume of the gas

                 N = number of moles

                R = 0.0821 liter atm/mole K

                T = Temperature

Hence, putting the given values into the above formula as follows.

   0.955 \times 31 \times 10^{-3} = N \times 0.0821 \times 295.15

                      N = 1.222 \times 10^{-3} moles

Now, the moles of hydrogen won't change. Therefore, let us calculate  volume at STP of 1.222 \times 10^{-3} moles of hydrogen.

Now, at STP T = 273.15 K , P = 1 atm  and N = 1.222 \times 10^{-3} moles

    1 \times V = 1.222 \times 10^{-3} \times 0.0821 \times 273.15 K

       V = 0.027398 Litre

         = 0.027398 \times 1000          (as 1 L = 1000 ml)

         = 27.398 ml

Therefore, volume of hydrogen at STP is 27.398 ml .

(c)  Now, we can write the the reaction for this case as follows.

         Mg + 2HCl \rightarrow MgCl_{2} + H_{2}

As, weight of magnesium = 0.028 grams

      Molar mass of magnesium = 24.3 grams/mole

   Number of moles of magnesium = \frac{mass}{\text{molar mass}}

                                             = \frac{0.028}{24.3}

                                             = 1.15226 \times 10^{-3} moles

Since, it can be seen from the reaction  that

    1 mole of Magnesium = 1 mole of hydrogen

and, moles of hydrogen = 1.15226 \times 10^{-3} moles

                                        = 0.001523 moles

Hence, theoretical number of moles of hydrogen that can be produced from 0.028 grams of Mg is 0.001523 moles

8 0
3 years ago
When the pressure of a gas decreases, which quantity will increase, assuming all other variables are held constant?
frosja888 [35]

I don't think the answer is in one of the options- unless I am reading it wrong and there is a 'V' option.

The volume (V) of gas increases when the pressure of the gas decreases assuming all the other variables are held constant.

I hope this helps!

7 0
3 years ago
Other questions:
  • PLEASE HELP<br> I really need someone to answer this!!!!
    11·2 answers
  • Technological advances in microbiology are providing evidence which indicates:
    6·2 answers
  • Is the following chemical reaction balanced?
    11·2 answers
  • if the side if a chemical equation has 3, carbon atoms, 6 oxygen atoms and 4 hydrogen atoms then the right side of the chemical
    5·1 answer
  • When starch is broken down it becomes _________.
    8·2 answers
  • Aside from Earth, which of the following inner planets once had liquid water on its surface?
    9·2 answers
  • You wish to make a 0.299 M hydroiodic acid solution from a stock solution of 6.00 M hydroiodic acid. How much concentrated acid
    7·1 answer
  • A sample of gas has an initial volume of 25 L and an initial pressure of 3.5 Pa. If the pressure changes to 1.3 Pa, find the new
    10·1 answer
  • An aqueous sodium acetate, NaC2H3O2 , solution is made by dissolving 0.395 mol NaC2H3O2 in 0.505 kg of water. Calculate the mola
    9·1 answer
  • Calculate the molarity of a solution prepared by dissolving 13.0 g of Na2CrO4 in enough water to produce a solution with a volum
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!