No. 1a. Atom 1 must be sodium (Na)
No. 1b. Atom 2 must me calcium (Ca)
No. 2 Isotopes are elements with theSAME NUMBER OF PROTONS but with DIFFERENT NUMBERS OF NEUTRON. The number of neutrons can be determined by SUBTRACTING the atomic number from the ATOMIC MASS. The mass number is THE TOTAL NUMBER OF PROTONS AND NEUTRONS.
3. The number of protons
Answer:
it is less than 1% made up of the world
Explanation:
i hope this helps u out
Answer:
Option D, 116 g of NaNO3
Explanation:
An unsaturated solution is the one in which the amount of salt dissolved in more than the maximum amount of salt that can be dissolved in it.
At 50 degree Celsius, 37 grams of salt can be dissolved in 100 ml of water. Hence, 116 gram of salt is the correct answer
Answer : The energy removed must be, 29.4 kJ
Explanation :
The process involved in this problem are :
![(1):C_6H_6(l)(322K)\rightarrow C_6H_6(l)(279K)\\\\(2):C_6H_6(l)(279K)\rightarrow C_6H_6(s)(279K)\\\\(3):C_6H_6(s)(279K)\rightarrow C_6H_6(s)(205K)](https://tex.z-dn.net/?f=%281%29%3AC_6H_6%28l%29%28322K%29%5Crightarrow%20C_6H_6%28l%29%28279K%29%5C%5C%5C%5C%282%29%3AC_6H_6%28l%29%28279K%29%5Crightarrow%20C_6H_6%28s%29%28279K%29%5C%5C%5C%5C%283%29%3AC_6H_6%28s%29%28279K%29%5Crightarrow%20C_6H_6%28s%29%28205K%29)
The expression used will be:
![Q=[m\times c_{p,l}\times (T_{final}-T_{initial})]+[m\times \Delta H_{fusion}]+[m\times c_{p,s}\times (T_{final}-T_{initial})]](https://tex.z-dn.net/?f=Q%3D%5Bm%5Ctimes%20c_%7Bp%2Cl%7D%5Ctimes%20%28T_%7Bfinal%7D-T_%7Binitial%7D%29%5D%2B%5Bm%5Ctimes%20%5CDelta%20H_%7Bfusion%7D%5D%2B%5Bm%5Ctimes%20c_%7Bp%2Cs%7D%5Ctimes%20%28T_%7Bfinal%7D-T_%7Binitial%7D%29%5D)
where,
= heat released for the reaction = ?
m = mass of benzene = 94.4 g
= specific heat of solid benzene = ![1.51J/g^oC=1.51J/g.K](https://tex.z-dn.net/?f=1.51J%2Fg%5EoC%3D1.51J%2Fg.K)
= specific heat of liquid benzene = ![1.73J/g^oC=1.73J/g.K](https://tex.z-dn.net/?f=1.73J%2Fg%5EoC%3D1.73J%2Fg.K)
= enthalpy change for fusion = ![-9.8kJ/mol=-\frac{9.8\times 1000J/mol}{78g/mol}=-125.6J/g](https://tex.z-dn.net/?f=-9.8kJ%2Fmol%3D-%5Cfrac%7B9.8%5Ctimes%201000J%2Fmol%7D%7B78g%2Fmol%7D%3D-125.6J%2Fg)
Now put all the given values in the above expression, we get:
![Q=[94.4g\times 1.73J/g.K\times (279-322)K]+[94.4g\times -125.6J/g]+[94.4g\times 1.51J/g.K\times (205-279)K]](https://tex.z-dn.net/?f=Q%3D%5B94.4g%5Ctimes%201.73J%2Fg.K%5Ctimes%20%28279-322%29K%5D%2B%5B94.4g%5Ctimes%20-125.6J%2Fg%5D%2B%5B94.4g%5Ctimes%201.51J%2Fg.K%5Ctimes%20%28205-279%29K%5D)
![Q=-29427.312J=-29.4kJ](https://tex.z-dn.net/?f=Q%3D-29427.312J%3D-29.4kJ)
Negative sign indicates that the heat is removed from the system.
Therefore, the energy removed must be, 29.4 kJ
Answer:
This is a correct answer. 2HCL + Fe = FeCl2 + H2