Many nitrogen atoms have seven neutrons<span> (14-7 = 7). Some atoms of nitrogen, however, have eight electrons. They are atoms of N-15, an isotope of nitrogen. In a neutral atom, the number of protons must equal the number of electrons.</span>
There are 1.2 moles of KBr found in 3 Liters of 0.4 M solution.
<h3>HOW TO CALCULATE NUMBER OF MOLES?</h3>
The number of moles of a substance can be calculated by multiplying the molarity by the volume.
No. of moles = Molarity × volume
According to this question, 3L of a KBr solution are contained in a 0.4M.
no. of moles = 3L × 0.4M = 1.2moles
Therefore, there are 1.2 moles of KBr found in 3 Liters of 0.4 M solution.
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Ca + Cl2 = CaCl₂
A synthesis <span>reaction.</span>
Velocity = 3.61 m/s
<h3>Further explanation</h3>
Given
mass of child = 35 kg
mass of sled = 5 kg
Kinetic energy = 260 J
Required
velocity
Solution
Energy because its motion is expressed as Kinetic energy (KE) which can be formulated as:
KE = 1/2.mv²
mass of object :
= mass child + mass sled
= 35 kg + 5 kg
= 40 kg
Input the value :
v²=KE : 1/2.m
v²= 260 : 1/2.40 kg
v²=13
v=3.61 m/s