What is the check all that apply?
Answer:
Explanation:
An element whose atomic number is 68 (number Z), has 68 electrons and 68 protons. According to the periodic table it corresponds to the element Erbium (Er), whose mass number (A) is 167. The number of neutrons is 167-68 = 99.
Answer:
The coefficient that should be inserted in front of chlorine is 2
Explanation:
Sn + 2Cl₂ → SnCl₄
As we have 4 atoms of chlorine in product side, we need 4 Cl in reactant side.
Chlorine is a diatomic atom, so if we have 2 mol of it, we are having 4 atoms of Cl.
The law of conservation of mass must be respected in every chemical equation
0.0018 grams is the mass of silver can 2 kJ of energy raise 15°C.
Explanation:
Data given:
heat supplied (q) = 2KJ or 2000 J
cp of silver= 0.24 j/gram °C (specific heat capacity is the amount of heat required to raise the temp of substance by 1 degree)
temperature = 15 degree centigrade
mass=?
using the equation for the heat capacity,
q= mcpT
m = 
Putting the values in the equation:
= 
= 0.0018 grams is the mass of silver in which 2 kJ of energy raise temperature by 15°C.
"Atoms have an equal proton and neutron charge."