I think the right answer is 2.5
Answer:
Column 17 halogens
Explanation:
To answer the question we need to know the following;
What are valence electrons?
- Valence electrons are outermost electrons in the outermost energy level of an atom of any element.
What are halogens?
- Halogens are group 7 elements that have seven valence electrons. They include, chlorine, fluorine, iodine, etc
What is the reactivity of halogens?
- Halogens are the most reactive non-metals in the periodic table. They react by gaining one electron to attain a stable configuration.
Answer:
c 18.0ml
Explanation:
The average mass of one H2O molecule is 18.02 amu. The number of atoms is an exact number, the number of mole is an exact number; they do not affect the number of significant figures. The average mass of one mole of H2O is 18.02 grams. This is stated: the molar mass of water is 18.02 g/mol.
Answer:
Yes, Mass is conserved.
Explanation:
Every chemical reactions obey the law of conservation of mass. The law of conservation of mass states that in chemical reactions, mass is always constant.
Equation:
2Na + Cl₂ → 2NaCl
From the equation above, one can observe that the reaction started using 2 atoms of Na and it produced 2 atoms of the same element in NaCl. A molecule of Cl produced 2 atoms of Cl in the NaCl
Design a simple experiment to support your answer:
Aim: To demonstrate the law of conservation of mass
One Na atom weighs 23g
Two Na atom will weigh 2 x 23 = 46g
1 atom of Cl is 35.5g
1 molecule of Cl containing two atoms of Cl will weigh 2 x 35.5 = 71g
Total mass of reactants = mass of 2Na + 1Cl₂ = (46 + 71)g = 117g
On the product side, Mass of 1 NaCl = 23+ 35.5 = 58.5g
Two moles of NaCl will give 2 x 58.5g = 117g
Since the mass on both side is the same, one can say mass is conserved.