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Which procedure could a student use to examine an intensive property of a rectangular block of wood

kirill [66]

An intensive property does not change when you take change when you take away some of the sample the producers that a student could use to examine the intensive property of a rectangular block of wood

6 0

3 years ago

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which statement best describes the equation caco3 2hcl → cacl2 co2 h2o? caco3 is a reactant; it is present before the reaction o

fomenos

Answer: $CaCO_3$ is a reactant; it is present before the reaction occurs.

Explanation:

In a chemical reaction the chemical formulas written before the arrow are described as reactants as they react together to form products which are written after the arrow.

$CaCO_3 + 2HCl \rightarrow CaCl_2 + CO_2 + H_2O$

Thus $CaCO_3$ and HCl are reactants here whereas $CO_2$ , $CaCl_2$ and $H_2O$ are products.

7 0

3 years ago

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Use the molar heat capacity for aluminum from table 1 to calculate the amount of energy needed to raise the temperature of 260.5

Nimfa-mama [501]

Unfortunately, you failed to include the table 1 from which the molar heat capacity of aluminum could have been obtained. However, as a general rule, the heat needed to raise the temperature of a certain substance by certain degrees is calculated through the equation,
H = mcpdT
where H is heat, m is mass, cp is specific heat capacity, and dT is change in temperature. From a reliable source, cp for aluminum is equal to 0.215 cal/g°C. Substituting this to the equation,
H = (260.5 g)(0.215 cal/g°C)(125°C - 0)
H = 7000.94 cal

6 0

3 years ago

Alveoli are tiny sacs of air in the lungs. Their average diameter is 4.50 × 10−5 m. Calculate the uncertainty in the velocity of

Arisa [49]

<u>Answer:</u> The uncertainty in the velocity of oxygen molecule is $4.424\times 10^{-5}m/s$

<u>Explanation:</u>

The diameter of the molecule will be equal to the uncertainty in position.

The equation representing Heisenberg's uncertainty principle follows:

$\Delta x.\Delta p=\frac{h}{2\pi}$

where,

$\Delta x$ = uncertainty in position = d = $4.50\times 10^{-5}m$

$\Delta p$ = uncertainty in momentum = $m\Delta v$

m = mass of oxygen molecule = $5.30\times 10^{-26}kg$

h = Planck's constant = $6.627\times 10^{-34}kgm^2/s^2$

Putting values in above equation, we get:

$4.50\times 10^{-5}m\times 5.30\times 10^{-26}kg\times \Delta v=\frac{6.627\times 10^{-34}kgm^2/s}{2\times 3.14}\\\\\Delta v=\frac{6.627\times 10^{-34}kgm^2/s^2}{2\times 3.14\times 4.50\times 10^{-5}m\times 5.30\times 10^{-26}kg}=4.424\times 10^{-5}m/s$

Hence, the uncertainty in the velocity of oxygen molecule is $4.424\times 10^{-5}m/s$

8 0

3 years ago

Select the keyword or phrase that will best complete each sentence. A tetrahedral carbon is____hybridized while a linear carbon

aivan3 [116]

Answer:

Explanation:

A tetrahedral carbon is__sp³__hybridized while a linear carbon is__sp___hybridized. Two different compounds that have the same molecular formula are known as___isomers____. Pi (π) bonds are generally_weaker (because they overlapped side ways)___than sigma (sigma) bonds. Hybridization is the combination of two or more__atomic ____orbitals to form the same number of__hybrid (combined s and p)__orbitals, each having the same shape and energy. A_pi (π)____bond is formed by side-by-side overlap of two p orbitals. The_electronegativity___is a measure of an atom's attraction for electrons in a bond and indicates how much a particular atom ''wants" electrons. Two Lewis structures that have the same atomic placement and a structure but a different arrangement of pi electrons are called_Resonance structure____. All single bonds are___sigma__bonds.

7 0

3 years ago