Answer:
On a periodic table, the columns of elements with similar properties are called groups
Na = 23 x 2.40 = 55.2
O = 16 x 2.40 = 38.4
H = 1 x 2.40 = 2.40
55.2 + 38.4 + 2.4 = 96
2.40 mol of NaOH = 96 amu
Answer:
Explanation:
Na react with H2O to form NAOH
2 Na+2H2O....................2NAOH + H2
Ca react with water and form calcium hydroxide
Ca + 2H2O........................Ca(OH)2
Mg react with water and form Magnesium hydroxide
Mg +2H2O .........................Mg(OH)2 however this coating of mg(oh)2 prevent it from further reaction
Fe react with water and form ferric hydride
3Fe +H2O.......................2 FeH +FeO
copper do not react with water
Answer:

Explanation:
Here, we want to convert J to cal
Mathematically:

Thus, to get our answer in cal, we divide the value given by 4.186
We have that as: