Thus, sound will travel at a slower rate in the denser object. If sound waves of the same energy were passed through a block of wood and a block of steel, which is more dense than the wood, the molecules of the steel would vibrate at a slower rate. Thus, sound passes more quickly through the wood, which is less dense.
6.4 times 10^-7 is the answer because you are moving your decimal places to the left so it will be negative 7
The products will be 
<h3>Chemical reactions</h3>
Zn is higher than hydrogen in the reactivity series. Thus, it will be able to displace hydrogen from the acid.
The equation of the reaction becomes: 
Hydrogen gas is released as a result. In fact, it is one of the ways of preparing hydrogen gas in the laboratory.
More on chemical reactivity can be found here: brainly.com/question/9621716
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The substance doesn't have a specific name. We just say that that substance is being reduced. Remember this mnemonic - OILRIG where "Oxidation is Loss, Reduction is Gain" of electrons.
Explanation:
Space exploration was aided most by the use of liquid fuel.
<em>Hope</em><em> </em><em>this helps</em><em>.</em><em>.</em><em> </em>
