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
mina [271]
3 years ago
12

Evidence of a chemical reaction includes all of the following EXCEPT: A. baking soda and vinegar release gas bubbles B. while ch

ewing a cookie, it becomes smaller pieces so you can swallow it C. heat is generated after mixing 2 chemicals
Chemistry
1 answer:
Bumek [7]3 years ago
3 0

Answer:

B.

Explanation:

Chemical reaction have to have either a temp change, formation of precipitate, formation of gas, or color change.

- Hope that helps! Please let me know if you need a further explanation.

You might be interested in
Which term best describes the rate at which global erosion takes place
dlinn [17]
The correct answer is slow
5 0
3 years ago
Cl2 + 2OH− → Cl− + ClO− + H2O
Nataly_w [17]
Cl2(g) -------> Cl-(aq) + ClO-(aq) 

2e- + Cl2(g) -------> 2Cl-(aq) [reduction] 

4OH-(aq) + Cl2(g) -----------> 2ClO-(aq) + 2H2O(l) + 2e- [oxidation] 
______________________________________... 
2OH-(aq) + Cl2(g) --------> Cl-(aq) + ClO-(aq) + H2O(l)
4 0
3 years ago
How many grams of dry nh4cl need to be added to 2.50 l of a 0.800 m solution of ammonia, nh3, to prepare a buffer solution that
tia_tia [17]

Answer:

The correct answer is 574.59 grams.

Explanation:

Based on the given information, the number of moles of NH₃ will be,  

= 2.50 L × 0.800 mol/L

= 2 mol

The given pH of a buffer is 8.53

pH + pOH = 14.00

pOH = 14.00 - pH

pOH = 14.00 - 8.53

pOH = 5.47

The Kb of ammonia given is 1.8 * 10^-5. Now pKb = -logKb,  

= -log (1.8 ×10⁻⁵)

= 5.00 - log 1.8

= 5.00 - 0.26

= 4.74

Based on Henderson equation:  

pOH = pKb + log ([salt]/[base])

pOH = pKb + [NH₄⁺]/[NH₃]

5.47 = 4.74 + log ([NH₄⁺]/[NH₃])

log([NH₄⁺]/[NH₃]) = 5.47-4.74 = 0.73

[NH₄⁺]/[NH₃] = 10^0.73= 5.37

[NH₄⁺ = 5.37 × 2 mol = 10.74 mol

Now the mass of dry ammonium chloride required is,  

mass of NH₄Cl = 10.74 mol × 53.5 g/mol

= 574.59 grams.  

8 0
3 years ago
Please help with the question above!
Sergio [31]

Answer:

B

Explanation:

B

7 0
3 years ago
Read 2 more answers
How many significant digits are in 89015
Lilit [14]

Answer:

Total 5 significant digits.

Explanation:

Significant digits are the numbers that give a meaningful contribution. For example, digit 013 has the 2  significant digits and zero is not a significant digit because digits 1 and 3 give meaningful contribution but digit zero does not value meaningful contribution. Similarly, the 89015 has a total of 5 significant digits and these digits are the 8, 9, 0, 1,  and 5.

6 0
3 years ago
Other questions:
  • A gas mixture contains HBr, NO2, and C2H6 at STP. If a tiny hole is made in the container, which gas will effuse fastest? NO2 C2
    12·1 answer
  • A volume of 25.0 mL of nitric acid, HNO3, is titrated with .12 M NaOH. To completely neutralize the acid 10.0 mL of NaOH must be
    15·1 answer
  • What is changed when matter undergoes a physical change?
    8·1 answer
  • Which temperature represents the highest average kinetic energy of the particles in a sample of matter ?
    9·1 answer
  • Y = 4x - 11 and y = -4x + 5*
    14·1 answer
  • A sample of sand, 5cm in diameter and 10 cm long, was prepared at a porosity of 50% in a constant head apparatus. The total head
    10·1 answer
  • Which statement best describes what happens during a chemical change?
    11·2 answers
  • If I fill a balloon with 5.2 moles of gas and it creates a balloon with a volume of 32.5 liters, how many moles are in a balloon
    13·1 answer
  • Identify the unit cell that has a = B = y = 90°.
    10·1 answer
  • If the mass ratio of nitrogen to hydrogen in ammonia is 4.7:1. if a sample of ammonia contains 10.0 gram of h, how many grams of
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!