Answer:
please brainlist answer
Explanation:
The addition of K 3 Fe(CN) 6 to a solution causes the formation of a deep blue precipitate which indicates that iron(II) ions are present.
If the value of H is positive, it means you have to add that much heat to complete the reaction. If H is negative, it means that much heat is released during the chemical process. Because it is -73 kJ, 73 kJ of heat are released in the reaction.
Answer:
0.109 g.
Explanation:
Equation of the reaction:
Na3PO4 + 3HCl --> 3NaCl + H3PO4
Number of moles of HCl = molar concentration × volume
= 0.1 × 0.04
= 0.004 mol.
By stoichiometry, 1 mole of Na3PO4 neutralises 3 moles of HCl. Therefore, number of moles of Na3PO4 = 0.004/3
= 0.0013 mol
Mass of Na3PO4 = molar mass × number of moles
= 0.0013 × 164
= 0.219 g
Since 50% of Na3PO4 was present in the sample. Let 100 g be the total mass of the substance
= 0.219 × 50 g/100 g
= 0.109 g.
Answer:
1 ) H2O 2) Hydrogen and oxygen 3) Compound
Explanation:
1) To write a chemical formula, you write the number of molecules of an element (2 hydrogen atoms + 1 Oxygen atom, or H2O). The letters represent the element's notation on the periodic table, while the number that follows it represents the number of atoms of that particular element within the compound. If there is no number that follows the letter, there is only one.
2) Letter "H" on the periodic table represents hydrogen, while "O" represents oxygen
3) You can tell that this is a compound because it is made of two or more elements found on the periodic table
compound name compound formula elements present
water H2O hydrogen (H) and oxygen (O)
ammonia NH3 nitrogen (N) and hydrogen (H)
carbon monoxide CO carbon (C) and oxygen (O)
carbon dioxide CO2 carbon (C) and oxygen (O)
