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
Triss [41]
3 years ago
15

Describe two ways he could change the metal physically and two ways he could change the metal chemically to try to identify it.

Chemistry
1 answer:
slega [8]3 years ago
6 0
Physical change is a change that occurs in a substance that does not change the identity of the substance. It does not alter the chemical structure of the molecules ehile chemical change involves the breaking of the bonds in the substance forming new substance. To identify a metal physically, we can use properties like their boiling and melting points. We can determine at what temperatures these metals melt or boil then from literature we compare the values. Another properties that can be looked upon to are hardness, color and density. For chemical methods, we can allow it to react with substances, that will produce precipitates containing the metal in question. Also, we can use other methods like titration method. All chemical methods involves the use of chemical reactions.
You might be interested in
In science what can only be separated by Chemical methods​
PilotLPTM [1.2K]

Answer:

A mixture is a physical combination of substances thus it only requires physical processes to separate.

5 0
3 years ago
5. What concentration of acid must be added to change the pH of 1 mM phosphate buffer from 7.4 to 7.3 (pKas of the phosphate buf
mr_godi [17]

Explanation:

According to the Henderson-Hasselbalch equation, the relation between pH and pK_{a} is as follows.

               pH = pK_{a} + log \frac{base}{acid}

where,     pH = 7.4 and pK_{a} = 7.21

As here, we can use the pK_{a} nearest to the desired pH.

So,      7.4 = 7.21 + log \frac{base}{acid}

             0.19 = log \frac{base}{acid}

            \frac{base}{acid} = 1.55

1 mM phosphate buffer means [HPO_{4}] + [H_{2}PO_{4}] = 1 mM

Therefore, the two equations will be as follows.

           \frac{HPO_{4}}{H_{2}PO_{4}} = 1.55 ............. (1)

  [HPO_{4}] + [H_{2}PO_{4}] = 1 mM ........... (2)        

Now, putting the value of [HPO_{4}] from equation (1) into equation (2) as follows.

             1.55[H_{2}PO_{4}] + [tex][H_{2}PO_{4}] = 1 mM

                        2.55 [H_{2}PO_{4}] = 1 mM

                             [H_{2}PO_{4}] = 0.392 mM

Putting the value of [H_{2}PO_{4}] in equation (1) we get the following.

                     0.392 mM + [HPO_{4}] = 1 mM

                          [HPO_{4}] = (1 - 0.392) mM

                              [HPO_{4}] = 0.608 mM

Thus, we can conclude that concentration of the acid must be 0.608 mM.

7 0
3 years ago
List one reason as to why historical growth has slowed in recent years.
hodyreva [135]
Lower fertility and longer lifespans steadily increased the potential labor force relative to the total population
4 0
3 years ago
Which of the following are in the human brain?
mezya [45]
The correct answer is D :)
5 0
3 years ago
Read 2 more answers
If 18.7ml of 0.01500M aqueous HCl is required to titrâtes 15.00ml of an aqueous solution of NaOH to the equivalence point, what
sweet [91]

Answer:

0.0187 M

Explanation:

Step 1: Write the balanced neutralization reaction

NaOH + HCl ⇒ NaCl + H₂O

Step 2: Calculate the reacting moles of HCl

18.7 mL of 0.01500 M HCl react.

0.0187 L × 0.01500 mol/L = 2.81 × 10⁻⁴ mol

Step 3: Calculate the reacting moles of NaOH

The molar ratio of HCl to NaOH is 1:1. The reacting moles of NaOH are 1/1 × 2.81 × 10⁻⁴ mol = 2.81 × 10⁻⁴ mol.

Step 4: Calculate the molarity of NaOH

2.81 × 10⁻⁴ moles are in 15.00 mL of NaOH.

[NaOH] = 2.81 × 10⁻⁴ mol/0.01500 L = 0.0187 M

6 0
3 years ago
Other questions:
  • Characteristics of matter that cannot be changed are called
    5·1 answer
  • A box of cleaning supplies weighs 15 N. If the box is lifted a distance of 0.60 m, how much work is done?
    13·2 answers
  • What is the fusing inside the sun to make helium
    5·2 answers
  • Half-reactions can be written to represent all
    10·2 answers
  • Is volume conserved​
    9·1 answer
  • Here is a word equation for a chemical reaction.
    5·1 answer
  • The metals that react violenty with cold water are
    11·1 answer
  • Analizando una biomolécula X, un científico comprueba que está formada por Carbono, Hidrógeno, Oxígeno y Nitrógeno, además de li
    10·1 answer
  • Label the following as a pure substance or a mixture.
    9·2 answers
  • Help, The question is down below
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!