Answer:
100ml of a stock 50% KNO3 solutions are needed to prepare 250ml of a 20% KNO3 solution.
Explanation:
In the given question it is mentioned that
S1=50%
V2=250ml
S2= 20%
We all know that
V1S1=V2S2
∴V1= V2×S2÷S1
∴V1= V2S2×1/S1
∴V1= 250×20÷50
∴V1= 100ml
Scientific laws and theories have different jobs to do. A scientific law predicts the results of certain initial conditions. ... In contrast, a theory tries to provide the most logical explanation about why things happen as they do.
Answer: 19.71 feet
Explanation:
Given: Speed of Charlotte =58.6 mi/h
Since 1 hour = 3600 seconds
and 1 mile = 5280 feet
So, Speed of Charlotte =
mi/ sec
She looks down at her phone and takes her eyes off the road for 4.36 s.
Since , Distance = 
So, Distance = 
Hence, Charlotte traveled 19.71 feet during this time.
Answer:
See explanation
Explanation:
The molecular equation shows all the compounds involved in the reaction.
The molecular equation is as follows;
2NaF(aq) + Pb(NO3)2(aq) -------> PbF2(s) + 2NaNO3(aq)
The complete ionic equation shows all the ions involved in the reaction
The complete ionic equation;
2Na^+(aq) + 2F^-(aq) + Pb^2+(aq) + 2NO3^-(aq) -------->PbF(s) + 2Na^+(aq) +2NO3^-(aq)
The net Ionic equation shows the ions that actually participated in the reaction
The net ionic equation is;
2F^-(aq) + Pb^2+(aq)--------> PbF(s)
Carbon filtering is a method of filtering that uses a bed of activated carbon to remove contaminants and impurities, using chemical adsorption. ... Active charcoal carbon filters are most effective at removing chlorine, particles such as sediment, volatile organic compounds (VOCs), taste and odor from water.