Answer:
1.)calcium+hydrochloric acid -->calcium chloride +hydrogen
2.)Ca + 2HCl -->CaCl2 + H2
3.)3.55g
Explanation:
1.) pretty self explanatory
2.)Ca + HCl -->CaCl2 + H2
then balance
Ca + 2HCl -->CaCl2 + H2 (+2 infront of Hcl)
3.) take calcium and calcium chloride
Ca + CaCl2
then you need the relative atomic mass of both
Ca=40
CaCl2=71 (40+(35.5x2))
Ca=40 40/40=1 1x2=2g
Then repeat that exact equation for calcium chloride
CaCl2=71 71/40=1.775 1.775x3=3.55g
The element with 4 protons in the nucleus in Beryllium.
Answer:
<u>225.6 kJ</u>, <em>assuming the water is already at 100 °C</em>
Explanation:
The correct answer to this question will depend on the initial temperature of the water to which heat is added to produce steam. Energy is required to raise the water temperature to 100°C. At that point, an energy of vaporization is needed to convert liquid water at 100 °C to water vapor at 100°C. The heat of vaporization for water is 2256.4 kJ/kg. The energy required to bring 100g of water from a lower temperature to 100°C is calculated at 4.186 J/g°C. We don't know the starting temperature, so this step cannot be calculated.
<em><u>Assuming</u></em> that we are already at 100 °C, we can calculate the heat required for vaporization:
(100.0g)(1000.0g/1 kg)(2256.4 kJ/kg) = 225.6 kJ for 100 grams water.
The answer for this one is a
Answer:
The answer is: D
Explanation:
A. They have the same number of electron energy shells. Is false, all the elements are in different periods so, they have different number of lectron energy shells.
B. They are all Halogens. No, is wrong, halogens are F, Cl ,Br
C. They have the same number of electrons. is wrong, if they had the same number of electrons they must be they same element and they aren't the same.
D. They are all Noble gases. Yes, it's true they are noble gases, they are the first group in the periodic table from the right.
