The two reason behind the invalidity of flame test are false positive and false negative.
while performing the flame test you must have to be accurate otherwise you will get false results may be positive for some element or may be negative in case the element is present. The main reason to get the false positive and false negative is the presence and contamination of sodium.
This compound is Boron selenate. Molar mass of B2(SeO4)3 is 450.4948 g/mol.
A defining feature of a material that is a good insulator would be its ability to stop or cancel an electric charge of another material. This happens because the molecules in the material are stable and there are no free electrons that would allow the charges to flow.
Answer:
1) The value of Kc:
C. remains the same.
2) The value of Qc:
A. is greater than Kc.
3) The reaction must:
B. run in the reverse direction to restablish equilibrium.
4) The concentration of N2 will:
B. decrease.
Explanation:
Hello,
In this case, by means of the Le Chatelier's principle which is based on the shift a chemical reaction could have under some modifications, we have:
1) The value of Kc:
C. remains the same, since it just depend the reaction's thermodynamics as it is computed via:

2) The value of Qc:
A. is greater than Kc, since the reaction quotient is:
![Qc=\frac{[N_2][H_2]^3}{[NH_3]^2}](https://tex.z-dn.net/?f=Qc%3D%5Cfrac%7B%5BN_2%5D%5BH_2%5D%5E3%7D%7B%5BNH_3%5D%5E2%7D)
Thus, the lower the concentration of ammonia, the higher Qc, making Qc>Kc.
3) The reaction must:
B. run in the reverse direction to restablish equilibrium, since ammonia was withdrawn and should be regenerated to reach the equilibrium.
4) The concentration of N2 will:
B. decrease, since less reactant is forming the products.
Best regards.
Answer:
b) C = 0.50 J/(g°C)
Explanation:
∴ Q = 50 J
∴ m = 10.0 g
∴ ΔT = 35 - 25 = 10 °C
specific heat (C) :
⇒ C = Q / mΔT
⇒ C = 50 J / (10.0 g)(10 °C)
⇒ C = 0.50 J/(g°C)