Chemical changes<span> occur when a substance combines with another to form a new substance, called </span>chemical<span> synthesis or, alternatively, </span>chemical <span>decomposition into two or more different substances.
So which one do you think is the answer?</span>
Answer:1.123 x 10^-31cm
Explanation:
mass of humming bird= 11.0g
speed= 1.20x10^2mph
but I mile = 1.6m
1km=1000
I mile = 1.6x10^3m
1.20x10^2mph= 1.6x10^3m /1mile x at 1.20 x 10^2
=1.932 x10^5m
recall that
1 hr= 60 min
1 min=60 secs, 1hr=3600s
Speed = distance/ time
=1.932 x10^5 / 3600= 5.366 x 10 ^1 m/s
m= a 11.0g= 11.0 x 10^-3kg
h=6.626*10^-34 (kg*m^2)/s
Wavelength = h/mu
= 6.626*10^-34/(11 x 10^-3 x 5.366x 10^1)
6.63x10^-34/ 590.26x 10 ^-3= 1.123 x10^-33m
but 1m = 100cm
1.123 x 10 ^-33 x 100 = 1.123 x 10^-31cm
de broglie wavelength of humming bird = 1.123 x 10 ^-31cm
Answer:
<h3>25.0 grams is the mass of the steel bar.</h3>
Explanation:
Heat gained by steel bar will be equal to heat lost by the water

Mass of steel=
Specific heat capacity of steel =
Initial temperature of the steel = 
Final temperature of the steel = 

Mass of water= 
Specific heat capacity of water=
Initial temperature of the water = 
Final temperature of water = 

On substituting all values:

<h3>25.0 grams is the mass of the steel bar.</h3>
Answer:
D.
Explanation:
D is the correct answer because, in aqueous solution, solvent is water and solute (in this example carbon dioxide CO₂) is a substance dissolved in water. The amount of solute that can be dissolved in a solvent depends of chemical composition, temperature and pressure