Answer:
Explanation: So, the atomic number is the number of protons present in an atom. For example, Helium's atomic number is 2, meaning it only has 2 protons. In most cases, the number of nuetrons and protons are equal, so Helium (usually) has 2 protons and 2 nuetrons - this is the nucleus. The atomic mass, or mass per nucleon is the proton and nuetron added together, so the atomic mass of Helium is about 4. Therefore, on the periodic table, as the atomic number increases by 1, the atomic mass increases by about 2 (the atomic mass is an average so it's not exact).
Answer : The mass of the water in two significant figures is, 
Explanation :
In this case the heat given by the hot body is equal to the heat taken by the cold body.
where,
= specific heat of iron metal = 
= specific heat of water = 
= mass of iron metal = 32.3 g
= mass of water = ?
= final temperature of mixture = 
= initial temperature of iron metal = 
= initial temperature of water = 
Now put all the given values in the above formula, we get
Therefore, the mass of the water in two significant figures is,
Metals are the type of elements that are most likely to form more than one type of ion, for instance iron can form the ion of Fe^2+ or Fe^3+.
Answer:
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Explanation:
you need battery, light bulb and wire in a close circuit
Answer: If it was 3 mol of solute in 2 L of solution it would be 1.5 mol/L.
However when the solute dissolves in the water creating the solution, the volume increases. So 3 mol of solute in 2 L of water creates more than 2 L of solution.
The correct method for making a 3 mol/L solution would be to place some water into a two liter volume container. Dissolve all 3 mol of the solute into the water. Then add water to the 2 L mark. Now there is 3 mol of solute and 2 L of solution.
Explanation: I hope this helps XDDDD
