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
Viktor [21]
3 years ago
14

Please help. I need someone smart

Chemistry
1 answer:
Sveta_85 [38]3 years ago
8 0
5678+910=13000
257-466=198
You might be interested in
What mass in grams would 5.7L of hydrogen gas occupy at STP?​
tekilochka [14]

Answer:  The correct answer is:  " 0.54 g " .

__________________________________________

Explanation:

Note that "hydrogen gas" is:  

H₂ (g)  ;   that is:  a "diatomic element" (diatomic gas) ;

_________________________________________

The molecular weight of "H" is:  1.00794 g ;

   (From the Periodic Table of Elements).

So, the molecular weight of:  H₂ (g)  is:

    " 1.00794 g * 2  = 2.01588 g ; {use calculator) ;

_________________________________________

Note the conversion for a gas at STP:

______

  1 mol of a gas = 22.4 L gas;

___

i.e. " 1 mol / 22.4 L " ;

____

So:     " 5.7 L H₂ (g)  *  \frac{1 mol H_{2} }{22.4 L} *\frac{2.01588 g}{mol} =? ;

The "L" ("literes" cancel out to "1" ;  since "L/L = 1 ;

The "mol" (moles) cancel out to "1" ; since "mol/mol = 1 ;

____

and we are left with:

____

 [5.7 * 2.104588 g ] / 22.4  =  ?  g ;

______________________

→ [ 11.9961516  g ] / 22.4 =

          0.53554248214  g ;l

_____________________________

We round this value to:  " 0.54 g " ;

 → since "5.7 L " has 2 (two) significant figures;  

     22.4 is an exact number conversion;

     and "5.7 L" has fewer significant figures than:

    " 2.104588 " ; or:  " 1.00794 " .

  → as such: We round to "2 (two) significant figures."

______________________________

Hope this is helpful.  Wishing you the best in your academic endeavors!

_______________________________

8 0
3 years ago
Catalytic converters made of palladium (pd) reduce automobile pollution by catalyzing the reaction between unburned hydrocarbons
Doss [256]
Unburned hydrocarbon on reacting with oxygen undergoes combustion reaction. However, the activation energy of this reaction is significantly high. When a catalyst like Pd is added to the reaction system, it provides active sites for the reaction to occur. It acts are a heterogeneous catalyst. It is pertinent of note that catalyst is refereed as heterogeneous, when it exist in different phase as compared to reactant and products. In present case, reactants and products are in gas phase, while catalyst is in solid phase. Due to availability of larger surface area at active site of Pd, activation energy of reaction decreases and decrease in activation energy favors higher reaction rates. 
3 0
3 years ago
A.<br> Na3PO4 + _HCI - H3PO, + _NaCl<br> What type of reaction and balance the equation
myrzilka [38]

Answer:

Molar Mass

Explanation:

5 0
2 years ago
Read 2 more answers
What can be used to determine the absolute age of two rocks? *
Aneli [31]

Answer:Ithink erosion cuz if we can tell how long ago it eroded we can see how old it is

Explanation:

6 0
3 years ago
Differentiate between Physical and chemical changes​
Marina CMI [18]

Answer:

<em>In a physical change the appearance or form of the matter changes but the kind of matter in the substance does not. However in a chemical change, the kind of matter changes and at least one new substance with new properties is formed.</em>

<h3> I HOPE THIS WILL HELP YOU IF NOT THEN SORRY HAVE A GREAT DAY:)</h3>

5 0
3 years ago
Read 2 more answers
Other questions:
  • Your chemistry experiment requires you to mix two chemicals in a test tube. To safely observe the chemical reaction you should:
    12·1 answer
  • How many moles of each substance are needed to prepare the following solutions?
    12·1 answer
  • What does an atomic number represent in an atom?
    10·1 answer
  • Calculate the mass of 9.75x1021 atoms of helium.
    12·1 answer
  • For the reaction N2(g)+O2(g)⇌2NO(g)N2(g)+O2(g)⇌2NO(g) classify each of the following actions by whether it causes a leftward shi
    12·1 answer
  • What are some examples of physical changes?
    14·2 answers
  • Iron sulfide is a compound. It is made by heating a mixture of iron and sulfur.
    15·1 answer
  • How many atoms are in 25.8 grams of Hg (mercury)
    10·1 answer
  • What is the mass of 1.20 x 10^25 atoms of He
    7·1 answer
  • Photosynthesis is an example of a
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!