Answer C
Exothermic reaction
Explanation
The general equation for an exothermic reaction is: Reactants → Products + Energy.
Answer
Hi there!
<u>Answer</u>:
Genes and chromosomes
Explanation:
All cells contain Genetic information (or Dna) which is organised into structures called chromosomes.
Chlorophyll are basically green pigments in Chloroplasts and both are <u>only</u><u> </u><u> </u><u> </u><u> </u>found in plant cells and not all cells
Answer:
8.90
Explanation:
Density = mass ÷ volume
D = 222.50 g ÷ 25.00
= 8.9
The density of the unknown metal is 8.90.
Hope that helps.
Answer:
A. 0.0655 mol/L.
B. PbBr2.
C. Pb2+(aq) + Br- --> PbBr2(s).
Explanation:
Balanced equation of the reaction:
Pb(NO3)2(aq) + 2NaBr(aq) --> PbBr2(s) + 2NaNO3(aq)
A.
Number of moles
PbBr2
Molar mass = 207 + (80*2)
= 367 g/mol.
Moles = mass/molar mass
= 3.006/367
= 0.00819 mol.
Since 2 moles of NaBr reacted to form 1 mole of PbBr2. Therefore, moles of NaBr = 2*0.00819
= 0.01638 moles of NaBr.
Since, the ionic equation is
NaBr(aq) --> Na+(aq) + Br-(aq)
Since 1 moles of NaBr dissociation in solution to give 1 mole of Br-
Therefore, molar concentration of Br-
= 0.0164/0.25 L
= 0.0655 mol/L.
B.
PbBr2
C.
Pb(NO3)2(aq)--> Pb2+(aq) + 2No3^2-(aq)
2NaBr(aq) --> 2Na+(aq) + 2Br-(aq)
Net ionic equation:
Pb2+(aq) + 2Br- --> PbBr2(s)