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
Alborosie
3 years ago
9

if the reduced row echelon form of the augmented matrix for a linear system has a row of zeros, then the system must have infini

tely many solutions. true or false
Chemistry
1 answer:
BigorU [14]3 years ago
7 0

Answer:

False

Explanation:

If the row echelon form of the augmented matrix for a linear system has a row of zeros, then the there must not have infinitely many solution,

we can prove this with an example. Suppose we have an augmented matrix A for linear system with a row of zeros,

             1     0      0      1

A=         0     1       0    -2

            0     0       1    - 1

            0    0       0     0

we get

x1=1

x2=-2

x3=-1

so, system has an unique solution.

we can take inference that the given statement is wrong

You might be interested in
Fe(s) + 2HCl(aq) --> FeCl2(aq) + H2(g)
soldier1979 [14.2K]

Answer:

In the option(A) moles of HCl left are 0.100 moles which is wrong, making the option incorrect.

Explanation:

Fe(s) + 2HCl(aq)\rightarrow  FeCl_2(aq) + H_2(g)


Moles of HCl = n

Molarity of HCl = 1.0M

Volume of HCl solution = 30.0 mL = 0.030 L (1 mL = 0.001L)

Moles=Molarity\times Volume (L)

n=1.0M\times 0.030 L=0.030 mol

Moles of Fe = \frac{0.56 g}{56 g/mol}=0.01 mol

According to recation , 1mol of Fe reacts with 2 mol HCl. Then 0.01 mole of Fe will recat with :

\frac{2}{1}\times 0.01 mol= 0.02 mol of HCl

This means that HCl uis in excess , hence excessive reagent.

Moles of HCl left unreacted :

= 0.030 mol - 0.020 mol = 0.010 mol

But in the option moles of HCl left are 0.100 moles which is wrong, making the option incorrect.

8 0
3 years ago
A sample of gas with an initial volume of 28.4 Liters at a pressure of 725 mmHg and a temperature of 305 K is compressed to a vo
Lerok [7]

Answer:

The final pressure is 2.25 atm or 1710 mm Hg

Explanation:

Step 1: Data given

The initial volume = 28.4 L

The initial pressure = 725 mm Hg ( = 725/760 atm) = 0.953947 atm

The initial temperature = 305 K

The new volume is 14.8 L

The new temperature = 375 K

Step 2: Calculate the new pressure

(P1*V1)/T1 = (P2*V2)/T2

⇒ with P1 = the initial pressure = 725 mmHg = 0.953947 atm

⇒ with V1 = the initial volume = 28.4 L

⇒ with T1  = The initial temperature = 305 K

⇒ with P2 = the new pressure = TO BE DETERMINED

⇒ with V2 = the new volume = 14.8 L

⇒ with T2 = the new temperature = 375 K

(0.953947 * 28.4)/305 = (P2 * 14.8)/375

P2 = 2.25 atm = 1710 mm Hg

The final pressure is 2.25 atm or 1710 mm Hg

6 0
3 years ago
Enter ionic and net equations: feso4(aq)+ na3po4(aq) arrow fe3(po4)2(s)+na2so4(aq)
stepan [7]

Answer:

<em> ionic equation : </em>3Fe(2+)(aq) + 3SO4(2-)(aq)+ 6Na(+)(aq) + 2PO4 (3-) (aq) → Fe3(PO4)2(s)+ 6Na(+) + 3SO4(2-)(aq)

<em> net ionic equation: </em>3Fe(2+)(aq)  + 2PO4 (3-)(aq) → Fe3(PO4)2(s)

Explanation:

The balanced equation is

3FeSO4(aq)+ 2Na3PO4(aq) → Fe3(PO4)2(s)+ 3Na2SO4(aq)

<em>Ionic equations: </em>Start with a balanced molecular equation.  Break all soluble strong electrolytes (compounds with (aq) beside them) into their ions . Indicate the correct formula and charge of each ion. Indicate the correct number of each ion . Write (aq) after each ion .Bring down all compounds with (s), (l), or (g) unchanged. The coefficents are given by the number of moles in the original equation

3Fe(2+)(aq) + 3SO4(2-)(aq)+ 6Na(+)(aq) + 2PO4 (3-) (aq) → Fe3(PO4)2(s)+ 6Na(+) + 3SO4(2-)(aq)

<em>Net ionic equations: </em>Write the balanced molecular equation.  Write the balanced complete ionic equation.  Cross out the spectator ions, it means the repeated ions that are present.  Write the "leftovers" as the net ionic equation.

3Fe(2+)(aq)  + 2PO4 (3-)(aq) → Fe3(PO4)2(s)

6 0
3 years ago
An unknown volume of gas has a pressure of 0.50 atm and temperature of 325 K. If the pressure is raised to 1.2 atm and the tempe
Grace [21]
You can solve this by using the equation (P1V1/T1) = (P2V2/T2). Plug in 0.50 atm for P1, leave V1 as the unknown, and plug in 325 K as T1. Then substitute 1.2 atm for P2, 48 L for V2, and 320 K for T2. Solve for V1, which is 117L, but since you round using two sig figs, your answer is C, 120 L. Hope this helps!
4 0
3 years ago
Whoever awser correct I will give you Brainly
vivado [14]

Answer:

Option A.

2Na + 2H2O —> 2NaOH + H2

Explanation:

To know which option is correct, we shall do a head count of the number of atoms present on both side to see which of them is balanced. This is illustrated below below:

For Option A:

2Na + 2H2O —> 2NaOH + H2

Reactant >>>>>>> Product

2 Na >>>>>>>>>>> 2 Na

4 H >>>>>>>>>>>> 4 H

2 O >>>>>>>>>>>> 2 O

Thus, the above equation is balanced.

For Option B:

2Na + 2H2O —> NaOH + H2

Reactant >>>>>>> Product

2 Na >>>>>>>>>>> 1 Na

4 H >>>>>>>>>>>> 3 H

2 O >>>>>>>>>>>> 1 O

Thus, the above equation is not balanced.

For Option C:

2Na + H2O —> 2NaOH + H2

Reactant >>>>>>> Product

2 Na >>>>>>>>>>> 2 Na

2 H >>>>>>>>>>>> 4 H

1 O >>>>>>>>>>>> 2 O

Thus, the above equation is not balanced.

For Option D:

Na + 2H2O —> NaOH + 2H2

Reactant >>>>>>> Product

1 Na >>>>>>>>>>> 1 Na

4 H >>>>>>>>>>>> 5 H

2 O >>>>>>>>>>>> 1 O

Thus, the above equation is not balanced.

From the illustrations made above, only option A is balanced.

7 0
2 years ago
Other questions:
  • Which statement is true about the plasma membrane?
    10·1 answer
  • 3. If an element has 47 protons and 54 neutrons what is the element and what is its atomic
    15·1 answer
  • When heated, solid copper(ii) carbonate decomposes to solid copper(ii) oxide and carbon dioxide gas. give the balanced chemical
    9·1 answer
  • Calculate the mass in grams of iodine (i 2 ) that will react completely with 20.4 g of aluminum (al) to form aluminum iodide (al
    10·1 answer
  • The voltage in a flashlight bulb is 6.0 volts and has a resistance of 24 ohms. Calculate the current
    8·2 answers
  • In the Dumas Method, the volatile sample
    12·1 answer
  • Which of these are ways in which a seed might be dispersed? Check all that apply. organisms clouds wind water rocks
    7·2 answers
  • Explain briefly how you would obtain crystals of sodium chloride from a mixture of sodium chloride ,lead[ii]oxide and iron filin
    14·1 answer
  • What is a technique for gene therapy?
    10·1 answer
  • The fuel used to power the booster rockets on space shuttles is a mixture of aluminum metal and ammonium perchlorate. the follow
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!