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
andrew11 [14]
4 years ago
13

Calculate what is the atomic number of a sodium atom that has 11 protons and 12 neutrons

Chemistry
1 answer:
fiasKO [112]4 years ago
4 0
The atomic number is 11. The atomic number will always be the same as the number of protons and electrons.
You might be interested in
The heat of combustion per mole for acetylene, C2H2(g), is -1299.5 kJ/mol. Assuming that the combustion products are CO2(g) and
guapka [62]

Answer: The heat of combustion per mole for acetylene is 227.7 kJ/mol.

Explanation:

The combustion equation of acetylene is as follows.

C_{2}H_{2} + \frac{5}{2}O_{2} \rightarrow 2CO_{2} + H_{2}O

Formula to calculate enthalpy of formation for a reaction is as follows.

\Delta H^{o}_{rxn} = \sum \Delta H_{products} - \sum \Delta H_{reactants}\\\Delta H^{o}_{rxn} = [2\Delta H^{o}_{f}(CO_{2}) + \Delta H^{o}_{f} (H_{2}O)] - [\Delta H^{o}_{f}(C_{2}H_{2}) + \frac{5}{2} \Delta H^{o}_{f} O_{2}]\\-1299.5 = 2(-393.5) + (-285.8) - \Delta H^{o}_{f} (C_{2}H_{2})\\\Delta H^{o}_{f} (C_{2}H_{2}) = 227.7 kJ/mol

Thus, we can conclude that heat of combustion per mole for acetylene is 227.7 kJ/mol.

3 0
3 years ago
How much of a sample remains after five half-lives have occurred?
timama [110]

Answer:

1/32 of the original sample

Explanation:

We have to use the formula

N/No = (1/2)^t/t1/2

N= amount of radioactive sample left after n number of half lives

No= original amount of radioactive sample present

t= time taken for the amount of radioactive samples to reduce to N

t1/2= half-life of the radioactive sample

We have been told that t= five half lives. This implies that t= 5(t1/2)

N/No = (1/2)^5(t1/2)/t1/2

Note that the ratio of radioactive samples left after time (t) is given by N/No. Hence;

N/No= (1/2)^5

N/No = 1/32

Hence the fraction left is 1/32 of the original sample.

3 0
3 years ago
In the chemical reaction NaHCO3 + CH3COOH → CH3COONa + H2O +CO2, 83 g of sodium bicarbonate reacts with 70 g of acetic acid. Whi
krok68 [10]
MNaHCO₃: 23+1+12+(48×3) = 84g
mCH₃COOH: 12+(1×3)+12+(16×2)+1 = 60g
.................
84g NaHCO₃ react with 60g CH₃COOH
83g NaHCO₃ react with...........

84g ----- 60g
83g ----- X
X = 59,29g CH₃COOH

We used 70g CH₃COOH, it' too much.
So, acetic acid is excess reagent, and sodium bicarbonate is limiting reagent.
_______________________________
B) Amount of CH3COOH is in excess.

:•)
3 0
4 years ago
What is the mass of the steel block?
Rzqust [24]

Answer:

190.2 grams

Explanation:

each arrow points to the amount it weighs, just add it all up

7 0
3 years ago
Read 2 more answers
What is 2(NH,4)Cr,2 O,7
Vitek1552 [10]

oxidation-reduction.


4 0
3 years ago
Other questions:
  • A house cat with a mass of 3.0 kg runs at a constant rate of 4.0 m/s in a straight line. What is the momentum of the cat?
    8·2 answers
  • Brad is testing three solutions with litmus paper. After dipping the litmus paper strips in the solutions, he observes two paper
    7·2 answers
  • What do all of these things have in common? ______________________________ Bird, dog, tree, person, flower, grass, bacteria, cat
    9·1 answer
  • Calculate the frequency of red light that has a wavelength of 700 nm.
    13·1 answer
  • How many miles of silver chloride are produced from 15.0 mol of silver nitrate?
    7·1 answer
  • Based on appearances, which group of animals likely has the greatest genetic diversity?
    10·2 answers
  • Shape of the periodic table
    15·1 answer
  • Carbon tetrafluoride (CF4) is a potent greenhouse gas. Draw a Lewis dot structure for this compound, explain the drawing, and pr
    6·2 answers
  • The group numbers for carbon oxygen, nitrogen and sulpher.​
    6·1 answer
  • (a) how many grams of water will be produced from the combustion of 3.36 g of ethane gas with 9.56 g of oxygen gas?
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!