Answer:
THE HEAT NEEDED TO CHANGE 3KG OF WATER FROM 10 C TO 80 C IS 877.8kJ OR 877,800 J.
Explanation:
Mass = 3.0 kg = 3 * 1000 = 3000 g
Initial temperature = 10 C
Final temperature = 80 C
Change in temperature = 80 - 10 = 70 C
Specific heat of water = 4.18 J/g C
Heat needed = unknown
Heat is the amount of energy in joules needed to change a gram of water by 1 C.
Heat = mass * specific heat * change in temperature
Heat = 3000 g * 4.18 J/g C * 70 C
Heat = 877 800 Joules
Heat = 877.8 kJ.
The heat needed to change 3 kg mass of water from 10 C to 80 C is 877,800 J or 877.8 kJ.
We have the compound: KSCN, Potassium thiocyanate, in an aqueous solution.
The dissociated reaction of the salt:
KSCN (aq) => K+ + SCN-
It has 2 ions. One of them is the potassium ion, K+ (cation) and the other one is the thiocyanate ion, SCN- (anion).
Answer:
K+, the potassium ion
SCN-, the thiocyanate ion
Answer:
The oxygen atom has a slightly negative charge.
Explanation:
3.5 - 2.5 = 1
For ionic bond electronegativity should be more than 1.6.
So, O and C do not have whole charge. Electronegativity of O more than C, so electrons slightly moved to the oxygen side.
Answer:
12.044 ×10²³ molecules of HCl
Explanation:
Given data:
Number of moles of MgO = 1 mol
Number of molecules of HCl react = ?
Solution:
Chemical equation:
MgO + 2HCl → MgCl₂ + H₂O
with 1 mole of MgO 2 moles of HCl are react.
Number of molecules of HCl react:
1 mole contain 6.022×10²³ molecules
2 mol × 6.022×10²³ molecules / 1 mol
12.044 ×10²³ molecules