I believe the correct answer from the choices listed above is the third option. Water is necessary for living organisms because all <span>organisms need water to transport chemicals into their cells. Hope this answers the question. Have a nice day.</span>
Answer:
See explanation
Explanation:
A. This is a neutralization reaction.
Molecular equation;
HBr(aq) + CsOH(aq) ---------> CsBr(aq) + H20(l)
Complete ionic equation;
H^+(aq) + Br^-(aq) + Cs^(aq) + OH^-(aq) --------> Cs^+(aq) + Br^- + H20(l)
Net ionic equation;
H^+(aq) + OH^-(aq) --------> H20(l)
B. This is a gas forming reaction;
H2SO4(aq) + Na2CO3(aq) ------->Na2SO4(aq) + H2O(l) + CO2(g)
Complete ionic equation;
2H^+(aq) + SO4^-(aq) + 2Na^+(aq) + CO3^2-(aq) ------->2Na^+(aq) + SO4^-(aq) + H2O(l) + CO2(g)
Net ionic equation;
2H^+(aq) + CO3^2-(aq) -------> + H2O(l) + CO2(g)
C. This a precipitation reaction
Molecular equation;
CdCl2(aq) + Na2S(aq) ------->CdS(s) + 2NaCl(aq)
Complete ionic equation;
Cd^2+(aq) + 2Cl^-(aq) + 2Na^+(aq) + S^2-(aq) ---------> CdS(s) + 2Na^+(aq) + 2Cl^-(aq)
Net ionic equation;
Cd^2+(aq) + S^2-(aq) ---------> CdS(s)
Answer:
ΔH3 = -110.5 kJ.
Explanation:
Hello!
In this case, by using the Hess Law, we can manipulate the given equation to obtain the combustion of C to CO as shown below:
C(s) + 1/2O2(g) --> CO(g)
Thus, by letting the first reaction to be unchanged:
C(s) + O2(g)--> CO2 (g) ; ΔH1 = -393.5 kJ
And the second one inverted:
CO2(g) --> CO(g) + 1/2O2(g) ; ΔH2= 283.0kJ
If we add them, we obtain:
C(s) + O2(g) + CO2(g) --> CO(g) + CO2 (g) + 1/2O2(g)
Whereas CO2 can be cancelled out and O2 subtracted:
C(s) + 1/2O2(g) --> CO(g)
Therefore, the required enthalpy of reaction is:
ΔH3 = -393.5 kJ + 283.0kJ
ΔH3 = -110.5 kJ
Best regards!
Answer:
8 Silicon atom are present in unit cell.
16 oxygen atoms are present unit cell.
Explanation:
Number of atoms in unit cell = Z =?
Density of silica = tex]2.32 g/cm^3[/tex]
Edge length of cubic unit cell = a = 0.700 nm = 

Molar mass of Silica = 
Formula used :
where,
= density
Z = number of atom in unit cell
M = atomic mass
= Avogadro's number
a = edge length of unit cell
On substituting all the given values , we will get the value of 'a'.
1 silicon is 2 oxygen atoms. then 8 silicon atoms will be 16 oxygen atoms.