Answer:
Explanation: When solutions of potassium iodide and lead nitrate are combined?
The lead nitrate solution contains particles (ions) of lead, and the potassium iodide solution contains particles of iodide. When the solutions mix, the lead particles and iodide particles combine and create two new compounds, a yellow solid called lead iodide and a white solid called potassium nitrate. Chemical Equation Balancer Pb(NO3)2 + KI = KNO3 + PbI2. Potassium iodide and lead(II) nitrate are combined and undergo a double replacement reaction. Potassium iodide reacts with lead(II) nitrate and produces lead(II) iodide and potassium nitrate. Potassium nitrate is water soluble. The reaction is an example of a metathesis reaction, which involves the exchange of ions between the Pb(NO3)2 and KI. The Pb+2 ends up going after the I- resulting in the formation of PbI2, and the K+ ends up combining with the NO3- forming KNO3. NO3- All nitrates are soluble. ... (Many acid phosphates are soluble.)
The mole ratio is 4 NO2 to 3 O2; 4:3
1) 2
2) 2
3) there are 2 atoms of hydrogen and 1 atom of oxygen, altogether is 3
4) subscript tells how many atoms of each element are present in the molecule
5) No, it is not balanced because the oxygen atom is not equal on both sides of the reactants and products. This wouldn’t be considered balanced as there are two oxygen atoms in the reactants section and only one oxygen on the products section.
It is:
2 H2 + O2 -> 2 H2O
Answer: 
Explanation: 1 gram is equal to 1000 Milligrams so

Since you go straight across its just multiplication so 0.00200x1000=200mg
To answer it in scientific notation it should just be
mg
Answer:
5
Explanation:
Count the digits after the first non zero number, any number after that (even zero) counts.
Hope that helped!!! k