Floor 19 is an isotope of fluorine It has different number of?————

Calculate the percent ionization of nitrous acid in a solution that is 0.311 M in nitrous acid (HNO2) and 0.189 M in potassium n

Alla [95]

HNO2 =====> H+ + NO2-
Initial concentration = 0.311
C = -x,x,x 
E = 0.311-x,x,x

KNO2 ====>K+ + NO2-
Initial concentration = 0.189 
C= -0.189,0.189,0.189 
E = 0,0.189,0.189

6 0

3 years ago

If a car can go from 0 to 60 mi/hr in 8.0 seconds, what would be its final speed after 5.0 seconds if its starting speed were 50

tangare [24]

Answer:

87.5 mi/hr

Explanation:

Because a = Δv / Δt (a = vf - vi/ Δt), we need to find the acceleration first to know the change in velocity so we can determine the final velocity.

vf = 60 mi/hr

vi = 0 mi/hr

Δt = 8 secs

a = vf - vi/ Δt

= 60 mi/hr - 0 mi/hr/ 8 secs

= 60 mi/hr / 8 secs

= 7.5 mi/hr^2

Now that we know the acceleration of the car is 7. 5 mi/hr^2, we can substitute it in the acceleration formula to find the final velocity when the initial velocity is 50 mi/hr after 5 secs.

vi = 50 mi/ hr

Δt = 5 secs

a = 7.5 mi/ hr^2

a = vf - vi/ Δt

7.5 = vf - 50 mi/hr / 5 secs

37.5 = vf - 50

87.5 mi/ hr = vf

7 0

3 years ago

The element carbon exists in several different forms. Pure carbon can be found in the form of diamonds, coal, and the graphite i

UNO [17]

Answer:

B) All carbon atoms have 6 neutrons.

Explanation:

The false statement from the given choices is that all carbon atoms have 6 neutrons.

There is a phenomenon called isotopy in chemistry.

Isotopy is the existence of two or more atoms of the same element having the same atomic number but different mass numbers due to the differences in the number of neutrons in their various nuclei.

These atoms of elements are called isotopes.
Carbon atoms generally have proton number of 6 which is the same as the atomic number.
As with all atoms, the mass number or atomic mass equals the number of protons and neutrons.

For the isotopes of carbon, their number of neutrons differs.

For example:

¹²₆C ¹³₆C ¹⁴₆C

The number of neutrons differs in the above isotopes.

Number of neutrons = mass number - atomic number;

¹²₆C , number of neutrons = 12 - 6 = 6

¹³₆C, number of neutrons = 13 - 6 = 7

¹⁴₆C, number of neutrons = 14 - 6 = 8

Therefore, based on the concept of isotopy, all carbon atoms do not have 6 neutrons.

7 0

2 years ago

The vapor pressure of water is 1.00 atm at 373 K, and the enthalpy of vaporization is 40.68 kJ mol!. Estimate the vapor pressure

Yuki888 [10]

Answer:

The vapor pressure at temperature 363 K is 0.6970 atm

The vapor pressure at 383 K is 1.410 atm

Explanation:

To calculate $\Delta H_{vap}$ of the reaction, we use clausius claypron equation, which is:

$\ln(\frac{P_2}{P_1})=\frac{\Delta H_{vap}}{R}[\frac{1}{T_1}-\frac{1}{T_2}]$

where,

$P_1$ = vapor pressure at temperature $T_1$

$P_2$ = vapor pressure at temperature $T_2$

$\Delta H_{vap}$ = Enthalpy of vaporization

R = Gas constant = 8.314 J/mol K

1) $\Delta H_{vap}=40.68 kJ/mol=40680 J/mol$

$T_1$ = initial temperature =363 K

$T_2$ = final temperature =373 K

$P_2=1 atm, P_1=?$

Putting values in above equation, we get:

$\ln(\frac{1 atm}{P_1})=\frac{40680 J/mol}{8.314J/mol.K}[\frac{1}{363}-\frac{1}{373}]$

$P_1=0.69671 atm \approx 0.6970 atm$

The vapor pressure at temperature 363 K is 0.6970 atm

2) $\Delta H_{vap}=40.68 kJ/mol=40680 J/mol$

$T_1$ = initial temperature =373 K

$T_2$ = final temperature =383 K

$P_1=1 atm, P_2?$

Putting values in above equation, we get:

$\ln(\frac{P_2}{1 atm})=\frac{40680 J/mol}{8.314J/mol.K}[\frac{1}{373}-\frac{1}{383}]$

$P_2=1.4084 atm \approx 1.410 atm$

The vapor pressure at 383 K is 1.410 atm

8 0

3 years ago

Which of the following polyatomic ions will form an ionic compound with a single sodium ion?

vaieri [72.5K]

Answer:

Option B, HCO3 1-

Explanation:

The valence of Sodium ion is +1 and the valence of HCO3 is -1. Thus, sodium ion has an extra electron to be donated to complete its outer shell while HCO3 needs an electron to complete its outer shell

Hence Na will combine with HCO3 to form NaHCO3

Option B is correct

5 0

2 years ago

Floor 19 is an isotope of fluorine It has different number of?—————